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Learn how to ganache a cake with this step-by-step tutorial! Including how to make ganache for a cake, how to use acrylic ganache boards to get perfect straight sides and sharp edges, plus all my favourite tips and tricks!
Ahh, ganache. Perfector of cakes and creator of sharp edges. And the cause of thrown spatulas and angry, frustrated curses.
When it comes to cake decorating I am most definitely a ganache girl. I do love me some buttercream, but when it comes to getting super straight sides and sharp edges, especially under fondant, ganache is my go-to.
It took me quite a while to become confident at ganaching cakes. I tried a few different techniques that were around at the time, but it wasn’t until I got some ganache boards and started doing my own hybrid method that I’m about to tell you about that it finally clicked for me, and I began getting consistent results every time.
If you’re brand new to using ganache, then this is the place for you! I will break down the benefits of using ganache on your cakes, how to make the ganache, how to prepare your cake, how to ganache your cake using ganache boards, how to store your ganached cake, and everything in between!
It takes a bit of practice, but before you know it, you’ll be ganaching cakes like a pro.
Because this is a detailed tutorial, I’m providing a table of contents below if there is a particular section you’d like to check out first. But if you’re new to decorating cakes with ganache, I definitely recommend grabbing a cup of whatever you enjoy drinking (tea… coffee… vodka, I don’t judge), and having a good read through the tutorial before you start on your cake.
I also have a follow-up Ganache FAQ post that may cover your questions if you don’t find the answer here.
Don’t let the length of this post put you off, I’ve simply broken everything down to make sure you have all the info you need, and each of the steps is easily achievable. You can do this. Promise!
Let’s get started!
Table of contents
- Why Use Ganache on a Cake?
- How To Make Ganache for Cake Decorating
- How to Ganache A Cake
Why Use Ganache on a Cake?
There are many benefits to using ganache rather than buttercream, but the main one as far as I’m concerned is this: stability.
Ganache, when made properly with the appropriate ratio for the weather conditions (don’t panic, I will explain all of that soon!) is firm at room temperature, which means it doesn’t need to be refrigerated. It is perfectly fine at cool room temperature for at least several days.
This means that if you cover your ganached cake with fondant you don’t need to worry about “cake/fondant sweating” as a refrigerated cake comes to room temperature. I’ll talk more below about how best to store your ganache covered cake.
In my opinion, there are two keys to successfully (and easily) ganaching a cake.
The first is to use a second cake board (or “ganache board”) on top of your cake while you ganache the sides. This ensures the sides will be perfectly straight and will help you get a nice sharp top edge when you flip the cake over after ganaching the top (please don’t panic if your eyes have crossed at the thought, I’ll be explaining the whole process step-by-step in just a few moments, and it will make much more sense!)
About Acrylic Ganache Boards
“Ganache boards” are acrylic boards that you place on the top of your cake, with your regular cake card or board underneath the cake. Then we apply ganache around the cake and use a scraper pressed against the two boards to scrape the excess ganache away, leaving perfectly straight sides.
Ganache boards should be the same size and shape as the cake card or board that you will be using on the bottom of your cake. While it’s helpful to have these acrylic boards because they are reusable, if you are just trying out this technique and don’t want to invest in ganache boards just yet, you can simply use a second cardboard cake card, the same size as you will be using on the bottom of the cake.
I have a set of white acrylic ganache boards that I used when I first shot the step-by-step photos for this tutorial in 2014, which I was kindly given by a friend in Australia and I’m unsure where she bought them from.
I have a second set of boards which are the ones I use most often and the ones pictured above, and I got them from Design at 409. I love Stacey’s boards, they’re super smooth on the edges, and I highly recommend you check them out if you’re in NZ, or happy to pay postage from NZ.
Ganache boards are pretty readily available in most countries now, so a quick Google search for “acrylic ganache boards” and the country you live in should find you some near you.
When you’re buying your ganache boards, make sure to check the measurements and compare them to the cake cards/boards you will be using and make sure they match. I use boards and cards that are whole-size measurements (6″, 7″, 8″ etc.) whereas some boards and cards are 1/4″ bigger (6.25″, 7.25″, etc.) for people who don’t want to trim the crusts off their cakes (these give space around the edges of the cake for the icing).
My preference is to buy the whole-size boards and trim the cake crusts. Whichever you choose, though, just make sure your cake cards and acrylic boards are the same size. And again, if you don’t want to buy the ganache boards, just use a second cardboard cake card instead.
Please note that my images from this post are being used by many online retailers to sell their ganache boards, but I do not endorse any of those products. The images are being used illegally and without my permission, so just keep in mind that even if you see images from this tutorial being used to sell these products, I haven’t used any of them, so I don’t recommend them. The only boards I use and can recommend from personal experience are the ones from Design at 409.
Ganache Consistency for Covering a Cake
The second key to great results when ganaching a cake is to get your ganache to the right consistency. And ‘right’ is a slightly subjective term – some decorators prefer a firmer ganache, and some like it really soft. I’m somewhere in between, so I tend to leave it a bit firmer for filling and then soften it a little more when I coat the outside of the cake. Once you’ve done a few cakes you will work out what the perfect consistency is for you.
As you’ll see below, there are two consistencies I like to use, one is similar to peanut butter, and one is a little softer, more like Nutella.
How To Make Ganache for Cake Decorating
If you’ve never made ganache before, then here is a quick intro on how to make it. There is no ganache ‘recipe’ as such, there are only two vital ingredients – chocolate and cream, and a ratio of how much of each to use.
The ratio controls how firmly the ganache will set – the higher the ratio of chocolate, the firmer it will set. More choc = firmer ganache.
Types of Chocolate For Ganache
To make ganache, you can use either compound chocolate or couverture chocolate (or, as I like to call it, “real chocolate”). Couverture choc is made with cocoa butter, whereas compound choc is made with various types of vegetable oil.
In my opinion, couverture tastes better, but compound makes a more stable ganache (less likely to split or separate). I often use a combination of both types of chocolate. I cover this in a bit more detail over in the ganache FAQ post.
Here in New Zealand, I like to use a combination of Whittaker’s chocolate and Nestlé compound chocolate buttons. I like the flavour of the “real” chocolate and the stability of the compound chocolate. Best of both worlds, y’all.
Ganache Ratios for Cake Decorating
For Dark Chocolate Ganache (chocolate with 50-60% cocoa solids is ideal) you need two parts chocolate to one part cream. In very warm weather you may need to increase this to two and a half or even three parts chocolate.
For Milk Chocolate Ganache (many milk chocolates don’t state the cocoa content, but around 30% is good) you need three parts chocolate to one part cream. In cooler weather – two and a half parts chocolate may be enough, and in warmer weather, you may need to increase it to three and a half or even four.
For White Chocolate Ganache you need three parts chocolate to one part cream. As with the milk chocolate ganache, in warmer weather, you may need to increase the chocolate to 3.5 – 4 parts in order to get a firm setting ganache. In super hot weather you may need to go as high as 5:1.
How Much Ganache Will I Need for My Cake?
To work out how much I need for each, I use the Ganacherator. There used to be a Ganacherator spreadsheet, which unfortunately doesn’t seem to be available to download anymore, but the website I linked to has the basic function of the spreadsheet.
Below is a screenshot example of the calculator. I used it to calculate the amount of ganache needed for a 7″ round cake, 4″ high with 4 layers of cake.
You simply input (1) the height you want the cake to be when finished, (2) the number of cake layers*, and the size of your cake. If it’s a round cake, just put the size in the first box (a) and leave the second box (b) blank. For a square or rectangle cake, you’ll put the second side measurement in the second box.
*If you’re not filling your cake, or filling it with something other than ganache, then put a “0” in the layers box, or a “1” if you want to make sure you have a bit of ganache left over for touch-ups.
Hit “calculate” and it will give you the total amount of ganache you need.
Below that it also has boxes to tell you how much chocolate and cream you’ll need, but it uses different ratios than I recommend, so I prefer to just ignore those boxes altogether and use the total ganache amount and the ratio chart above to work out how much cream and choc I need.
Here’s an example of how to work out the amount of chocolate and cream needed:
EXAMPLE: If you were making an 7″ round cake with four layers of cake (and therefore 3 layers of ganache filling) you would need approximately 1430g (1.43kg) of ganache to fill and cover it. I’m rounding up to 1500g for ease of calculating, plus it’s better to have too much ganache than not enough. The ganache needs to set after being made, so if you have to make more ganache while in the middle of ganaching your cake, you’re going to have to take a pause while your ganache sets.
Dark chocolate ganache is a 2:1 ratio, which is 3 ‘parts’ in total. To work out how much chocolate and cream you need, you just divide 1500g by 3, which is 500g, so that is how much cream you need (one ‘part’ cream) and you need twice as much chocolate (2 ‘parts’ chocolate), so 500g times 2 is 1000g.
So for 1500g of dark chocolate ganache, you will need 1000g of chocolate and 500g of cream.
There are many methods for making ganache, but this is what I do:
Chocolate Ganache For Cake Decorating
Dark Chocolate Ganache
- 2 parts chocolate
- 1 part cream
Milk Chocolate Ganache
- 3 parts chocolate
- 1 part cream
White Chocolate Ganache
- 3 parts chocolate
- 1 part cream
- Chop the chocolate into smallish (roughly half an inch or less) pieces.
- Find yourself a saucepan big enough to hold all of your cream and chocolate, and weigh the cream straight into it. Place the pan over a medium-high heat and bring it just to a boil. The bubbles should cover most of the cream’s surface. Make sure you watch it carefully, once it comes to the boil it can quickly boil over. Remove from the heat and leave it until the bubbles stop.
- Add the chopped chocolate to the pan, and gently shake the pan until the chocolate is mostly covered by the cream. Don’t stir it yet, just leave it to sit and melt for a few minutes.
- Gently stir with a silicone spatula (or use a wire whisk for dark chocolate ganache, as it is softer). Keep stirring until the chocolate and cream fully combine and become smooth.
- If there are still unmelted pieces of chocolate in the ganache, place the pan back over a very low heat, and stir constantly until no lumps remain and the ganache is glossy and smooth.
- If you happen to own a stick mixer/hand blender, then you can use that to give the ganache a quick blitz to ensure all the chocolate is melted and that the emulsion is smooth.If you want to colour the ganache, you can do that now.
- Pour the ganache into a microwave-safe bowl, leave to cool then cover with plastic wrap on the surface of the ganache and leave overnight at room temperature to set.
- If you don’t have time to let the ganache set at room temperature then you can speed it up by putting it in the fridge – just make sure you stir it often so that it cools and sets evenly.
- You can store the ganache at room temperature for a couple of days, or refrigerate it for a month or so, or freeze it for a little longer. These time frames are an indication only and could vary depending on the ingredients used and storage temperatures, so you will need to use your discretion when storing.
- The first thing to try to correct it is to use a stick mixer/hand blender, just place it in the ganache and blend it until the ganache has come together and is smooth. Once it is smooth, stop blending, otherwise, you will incorporate too much air.
- If that doesn’t work, there are a couple more things you can try. The first is to add a splash more cream and mix, this may bring the ganache back together. You may need to add even more cream, in which case just bear in mind that your ganache will not set as firmly.
- You can also try popping the ganache into the fridge, stirring every 10 minutes or so, and the ganache may emulsify again.
Once you’ve made your ganache and it has set overnight, you can move on to the fun and messy bit, ganaching your cake!
If it is your first time ganaching a cake and this all looks like it will never click, and you think you’ll never be able to get these super sharp edges, then I am here to tell you that you most definitely can. All it takes is practice.
How to Ganache A Cake
In this tutorial, I have shown how to ganache a round cake. I use the exact same method when ganaching a square cake, it just takes a little more time and effort at the corners to get them perfectly straight and square.
What you’ll need:
- Your cake
- Two cake boards the same size as your cake (or one cake board and one acrylic ganaching board)
- 90° angled cake scraper (stainless steel, acrylic or rigid plastic)
- Baking paper/non-stick parchment
- Offset spatula
- Pencil & scissors
- Cutting board, bread knife (or whatever you like to use to split your cakes into layers) and small serrated knife
- Two setup boards or masonite cake boards several inches larger than your cake (to keep your turntable clean)
- Pieces of non-slip mat – one piece to go between your turntable & setup board, and one piece slightly smaller than your cake board
- Spirit level
During this tutorial I will refer to the board on the base of the cake (the one your cake will stay sitting on once you’re done ganaching) as the “cake board”, and the board that starts out on top of the cake as the “ganache board”. If you’re using a second cardboard cake card instead of an acrylic ganache board, then I recommend writing “ganache board” onto the bottom of that board the first time you do this technique, so you’ll be able to keep track of which board I’m talking about when we flip the cake over.
Trace around your ganache board onto a piece of baking paper, fold it into quarters and cut out the circle. Unfold it and attach it to the ganache board using a few dabs of ganache and put this in the fridge to set the ganache. This board will be the ‘lid’ that helps to give perfectly straight sides to your cake, and the paper will make it easy to remove the board when you’re ready.
Split your cake into layers. You can do this any way you like. I recently invested in an Agbay cake leveller, but up until then I used the toothpick method: Just measure the height of the cake and use toothpicks to mark the height of the layer you want to cut, then go around with the bread knife, resting it on the toothpicks and slowly cutting through to the centre. Repeat for each layer.
I generally split my standard height cakes into four layers, and for this particular cake, the layers were just a little under one inch thick. I usually aim for between ¾ -1” thick cake layers.
Use a small serrated knife to trim the edges of each layer so that the layers are 1/2” smaller than the size of your cake board. I now use trimming rings to make this faster, but prior to that, I used plastic templates that I made and show in the picture below.
To make these, I just drew around cake boards onto some thin plastic cutting boards, and cut out the circles 1/4″ inside the lines.
Trimming your cakes will make sure you have an even 1/4” layer of ganache all around the cake, and no chance of any cake protruding through the ganache and ruining your perfect finish (and possibly compromising the stability of your cake).
This also removes any crusty or dark edges from your cake, making it prettier when sliced. (Of course, if you’ve used baking strips on your cake, you shouldn’t have any crusty edges!)
Gently warm the ganache in the microwave, stirring regularly, until it softens to the consistency of peanut butter. I like to use low-medium power so the ganache doesn’t accidentally melt too much.
Place a piece of non-slip mat between your turntable and setup board, and then place the cake board on top, securing with the smaller piece of non-slip mat.
Attach your first layer of cake to the board with a dab of ganache, then fill and stack all your cake layers. Obviously, if you’re filling with something other than ganache and just ganaching the outside, then just do whatcha do with your chosen filling.
Try to keep your layers of filling even, but don’t panic if the cake isn’t perfectly level on top when they’re all stacked, we’ll make it level later.
Get down to eye level with your cake and turn it around slowly to check that your cake layers are reasonably well lined up, and none stick out too far out the side (if they stick out, then the ganache layer won’t be even and you can have issues with bulging. Trust me, just check they’re all lined up, and if they’re not – either squish ‘em back into place or trim them down with a knife.
Add a few dab of ganache to the baking paper covered ganache board, then place it on top of your stacked layers, and gently press down to settle the cake. Use a right angle or scraper to make sure the board is centred and lines up with the bottom board and to check that your cake layers don’t stick out any further than the boards.
Have a look at the gap between the cake and the ruler in the image below. You want it to have that nice gap there that we will fill in with ganache.
Brush off the worst of the crumbs from around the cake, then refrigerate the cake until the ganache layers firm up slightly and the top cake board doesn’t move.
It’s also a good idea when you put it in the fridge to place a bit of weight on top of the cake. This helps settle the cake layers and the filling and can prevent the cake from bulging later on. I find that using a couple of plates (dinner size for big cakes, small/side plates for smaller cakes) will evenly settle the cake. Just pop them on top of the ganache board after you’ve put the cake into the fridge. (I say ‘after’ because there was this one time that I put them on first, and then they almost slid off the cake and onto the floor as I carried it to the fridge. Don’t be like me.)
Once it’s firm, we can move on to ganaching the sides.
Warm the bowl of ganache up again, if necessary, and start applying the ganache to the sides of the cake. Start at the top, holding the top board with one hand and press the ganache up against the board, then continue around the whole top edge of the cake, being careful not to let your spatula touch the cake or you may pick up crumbs.*
*If you want to, you can do a “crumb coat” of ganache – just spread a thin layer of ganache around the cake to seal in any crumbs, let it set for a bit in the fridge, and then add the rest of your ganache. I skip this step because I’m lazy… and like to live on the wild side.
Add more ganache so that the layer is very thick, coming out past the cake boards. Yep, really slap that good stuff all over.
(You can still see the lip of the bottom board, needs more ganache!)
Hold a scraper against the cake so that it rests on both cake boards. Scrape gently, turning the turntable with your other hand, until you’ve removed the excess ganache. Remember to just leave your hand where it is, and let the turntable do the work.
Put the excess ganache back into the bowl, then rinse and dry your scraper and scrape again.
There may be some little air bubble holes (you can see some on the left side of the cake in the picture below), so just fill them in with some more ganache and scrape again, rinsing and drying the scarper each time. Keep going until you’re happy with the sides.
Once the sides are smooth, pop the cake in the fridge until the ganache is firm. It should feel firm and set when you press it lightly with your finger.
Slide a spatula between the ganache board and the piece of baking paper. Glide the spatula all the way around the top edge of the cake until the board pops off.
Find a spot on the cake where the baking paper is lifted up (or flick up an edge with your finger or spatula) and peel off the circle of paper.
Warm the bowl of ganache again until it is quite soft, like Nutella (y’know, like smooth peanut butter that’s been left in a hot kitchen. Kinda smooshie. Very technical, I know). We want it soft enough that it will squish out a bit when you flip the cake over.
Spread a thick layer (at least ½”/1cm) of ganache over the top of the cake, spreading it so it goes a little over the edges of the cake.
You don’t need to make it perfect but just try for a somewhat even layer of ganache across the whole top surface.
Place a large piece of baking paper over the top of the cake, starting at one edge and smoothing out as many air bubbles as you can.
Place another setup board on top, and carefully flip the cake upside down.
Pop a spirit level on top of the cake and gently press on the cake until the cake is level and the ganache squishes out the bottom a little.
I like to take this opportunity to clean any ganache off the bottom of the cake board (which is now on the top, stay with me now). This saves getting it smeared onto your display board or another tier of cake if you need to shimmy it over when you assemble the cake later.
Warm the scraper slightly under warm water, place it gently against the cake and scrape away the excess ganache. Make sure you keep the scraper straight or you will scrape away those lovely straight sides!
If there are any gaps along the edge you can just dab in a bit more ganache, and scrape it again.
Check out that sharp edge we’re getting!
Refrigerate the cake again until the ganache is nice and firm.
Flip the cake back over and peel off the baking paper. Fill in any little holes on the top of the cake with more ganache and smooth with the spatula.
Warm up your scraper and scrape once more around the sides of the cake.
You may end up with a little ridge of ganache along the top edge which you can either carefully scrape off with your metal spatula, or warm up the spatula and smooth the ridge of ganache back across the top of the cake. Make sure the ganache is still cold and firm when you do this, so there is less chance of accidentally messing with the sharp edge.
Alternatively, you can let the ganache set completely, then lay a metal spatula or a small sharp knife flat against the top of the cake and slice the ridge off.
Warm the spatula in hot water one last time and use it to smooth any imperfections.
Leave the ganached cake to fully set before decorating. When covering with fondant it’s best to let the fondant set overnight.
How to Store a Ganache Covered Cake
Exactly how you store your cake will depend on the specific cake and filling recipes you’re using.
A ganache-covered cake does not need to be refrigerated unless you have filled it with some kind of perishable filling, such as fresh fruit or a fruit compote, or if you live in a particularly hot climate and don’t have air conditioning.
As a rule of thumb, (unless you’re using a perishable filling) you can store your ganached cake at cool room temperature, ideally in a cake box or clean cardboard box to keep dust (and pets, and children) away from it. Putting it in a cupboard works too.
If you do need to chill the ganached cake and you want to cover it in fondant, make sure you bring the cake back to room temperature before you try to cover it, otherwise, your fondant will get sticky with condensation (and you will get sad).
So that is how to ganache a cake and get sharp edges. Now you can go off and cover it in fondant, or simply sit back and admire your ganache handiwork!
If you’re not sure what to use to make your fondant stick to your perfect ganache, then check out this little mini tutorial, where I wrote a list of things you can use, with pros and cons of each to help you make your choice.
If you have any questions you can check out my Ganache FAQ post, where I’ve rounded up all of the questions I’ve been asked most about this technique, but if your question isn’t answered there then feel free to ask me in the comments below 🙂