I wanted to learn how to make mousse because I’ve never really made it before.
But I didn’t want to just make a regular degular mousse, I wanted something more exciting. So I made a chocolate mousse cake. This cake had a layer of chocolate cake at the base, a layer of a chocolate mousse and then a milk chocolate ganache on top.
IT WAS SO LIGHT AND FLUFFY, so soft and soooo chocolaty.
The cake layer
The first thing we are going to make is the chocolate cake layer, because this needs time to bake and cool.
I went with chocolate cake because I wanted this mousse cake to be very chocolaty, but any kind of cake works. You can use whatever flavour you want.
Here are the ingredients I used to make the chocolate cake layer:
- Cocoa powder
- Instant coffee – this is going to help intensify the chocolate flavour.
- Hot water – we’re going to mix this with the cocoa powder. This will also intensify the chocolate flavour.
- Oil – this is going to add moisture. Any flavourless oil works but I always use vegetable oil.
- Buttermilk – also for moisture.
- Plain flour – also known as all purpose flour.
- Sugar – I used a mixture of both white and brown sugar. The brown sugar is going to add extra flavour and again….moisture.
- Baking soda
- Vinegar – this is going to react with the baking soda as the cake bakes, giving you a fluffier cake.
There are some ingredients that I use for my chocolate cake, that I usually get asked if there are any substitutions for. So let’s quickly talk about them:
All the coffee does is intensify the chocolate flavour in the cake, it makes it taste more chocolaty.
It doesn’t make this cake taste coffee flavour, we’re not using enough so you won’t taste it.
So if you don’t like the taste of coffee, you don’t need to worry about this.
With that being said, you can leave it out if you want to. It won’t make a huge difference to the cake.
I like to add buttermilk to my chocolate cakes, just because it adds a lot of moisture.
If you didn’t have buttermilk, plain natural yoghurt is the best substitute. To be honest, most of the time I do just use yoghurt.
If you didn’t have either, you can make a buttermilk substitute.
To do this just get 60ml of whole milk and mix 1/4 tablespoon of lemon juice or vinegar into this. Leave this aside for 10 minutes, then it is ready to use.
BUTTTT using actual buttermilk or plain yoghurt will give you the best results.
The last thing we are going to do when making the cake layer is mix some baking soda and vinegar together. Then this goes into the cake batter.
As the cake bakes, this vinegar will react with the baking soda, which is going to give the cake an extra lift. This will give your cake extra fluffiness and a velvety texture.
I use white vinegar for this, but apple cider vinegar works great too.
If you didn’t have either, lemon juice works as well, but I do think vinegar gives better results.
I’ve learnt that mousse is not the easiest thing to make.
And by not easy, I mean nothing about it is difficult, there are just a lot of steps.
Let me just give a quick overview of what we are going to be doing.
Essentially, in one bowl we’re going to whip some cream. In a separate bowl we’re going to whip some egg whites. Then in a third bowl, we’re going to mix the rest of the ingredients, then mix everything together.
So again it’s not hard to make, there are just quite a few steps and a lot of washing up to do after.
But anyway, these are the ingredients you will need for this:
- Double cream – also known as heavy cream.
- Egg whites
- Cream of tartar – this is going to help stabilise your whipped egg whites. You can leave it out if you wanted to, but I really do recommend using it.
- Granulated sugar – caster sugar works too.
- Chocolate – we’re using a mixture of both dark and milk chocolate.
- Egg yolks
- Vanilla – for some extra flavour.
- Salt – just a little bit to help enhance the flavours.
A few tips when making the mousse
Don’t over whip your cream
The first step is to whip your cream.
You only want to whip this until your cream is smooth, thick, and has firm peaks.
I’ve you over whip this, the cream will be too thick and not very smooth, we don’t want this.
It will make it hard to fold into the rest of the ingredients, and it will effect the final texture of the mousse.
So try not to over whip it.
But with that being said, if you do over whip it slightly, don’t worry about it too much. It’s not a huge deal, the mousse will still taste great.
Loosen your chocolate mixture
At some point in the process of making the mousse, we’re going to mix together the melted chocolate, egg yolks, salt and vanilla together.
When you start mixing this, you will see the mixture thicken. It will become quite thick.
After this, we want to gently fold in our whipped cream and then the whipped egg whites.
The problem is, at this point the chocolate mixture is too thick, so it is difficult to fold anything into it.
So we want to loosen the chocolate mixture first.
To do this, just add a large dollop of the whipped cream into it and whisk this in, until the mixture is smooth.
Now you can add the rest of the whipped cream and fold this in with a spatula. Then fold in the egg whites.
Fold in the whipped cream and whipped egg whites gently
We want our mousse to be light, fluffy and airy.
This light, fluffiness and airiness is coming from the whipped cream and whipped egg whites.
We have whipped a lot of air into these, so when we start folding it into our chocolate mixture, we don’t want to knock all of this air out.
So make sure to fold it in gently with a spatula. It might take some time, but like…enjoy the process you know.
The final layer of this cake is a milk chocolate ganache.
I wanted a third layer, so I added a ganache. It this layer necessary…no not really. But I added it anyway.
Making this is super easy, you just want to heat some milk chocolate and cream together.
Once the chocolate is all melted and smooth, add it onto your mousse layer.
Leaving the mousse cake to set overnight
IT IS SO IMPORTANT TO LEAVE YOUR CAKE TO SET IN THE FRIDGE OVERNIGHT.
Please don’t skip this step. If you try taking the cake out of the tin too early, it will be a disaster.
The mousse needs enough time to fully set up, so it is best to leave it in your fridge overnight.
But then the next day you can take it out of the tin, add some whipped cream on top if you want to, then cut into it!