White Chocolate Mousse Cake

A few weeks ago I made a chocolate mousse cake. When I posted that video, a lot of people were telling me to make a white chocolate mousse cake next.

So here we are. This cake has a layer of vanilla cake at the base, a layer of a light fluffy white chocolate mousse and then some whipped cream piped on top.

IT WAS SO GOOD, if you like white chocolate and if you like mousse, you need to try this!

A slice of the white chocolate mousse cake on a white plate, with the full cake in the background.

Video Tutorial

The cake layer

We’re going to start by making the vanilla cake layer because this needs time to bake and cool.

Here are the ingredients I used for this:

  • Unsalted butter – you want to make sure this is softened.
  • Oil – any flavourless oil works but I like to use vegetable oil.
  • Granulated sugar – caster sugar works too.
  • Vanilla extract
  • Eggs
  • Self raising flour – I will talk about how to use plain/all purpose flour in the next section.
  • Milk
The top of the mousse cake.

The self raising flour

I like to use self raising flour for my vanilla cake batter. I find it easier to use because I don’t have to add any raising agent, they have already been added.

But if you don’t have any self raising flour, or if you live in a place where it is hard to find, plain/all purpose flour can be used.

Use the same amount but mix 2 teaspoons of baking powder and 1/8 teaspoon of salt into it.

Now it is ready to use.

The cake batter inside of a cake tin, before being baked.
The cake layer inside of the tin, after being baked.

The white chocolate mousse

The mousse is pretty simple to make, but there are a few different parts to it.

But again, it is simple to make.

These are the ingredients you will need for it:

  • Double cream – also known as heavy cream.
  • Egg whites
  • Cream of tartar – this is going to help stabilise your whipped egg whites. I recommend using it, it helps a lot, but you could leave it out if you wanted to.
  • Granulated sugar – caster sugar works too.
  • White chocolate
  • Egg yolks
  • Vanilla extract
  • Salt – a small amount to help enhance the flavours.
The ingredients needed to make the white chocolate mousse.

A few tips to remember when making the mousse 

Don’t over whip your cream and egg whites

The first steps in making the mousse is to whip the cream and then to whip the egg whites.

You want to make sure to not over whip both of these.

As soon as they reach stiff peaks, stop whipping them. If you over whip them, it’ll effect the final texture of your mousse.

Loosen the chocolate mixture 

We’re going to melt our white chocolate, then mix some egg yolks into it.

This mixture is going to become super thick.

So to loosen this, get a dollop of your whipped cream and whisk this into the white chocolate mixture.

This will loosen the mixture, making it easier to fold the rest of the cream and egg whites into it.

Fold the whipped cream and egg whites in gently

The last step is to fold in the whipped cream and then the whipped egg whites.

The cream and the egg whites are going to give your mousse its fluffiness and creaminess.

So you want to make sure to fold them in gently, you don’t want to deflate them.

The white chocolate mousse after it was added into the tin.

Leaving the mousse cake to set overnight

Once your mousse has been made, add your cake layer into a springform tin, then add the mousse on top.


The mousse needs time to set, if you try taking your cake out of the tin too early, it will be a disaster. The mousse will fall apart.

So make sure to give it a chance to set.

But then the next day it is finally done, you can add some whipped cream on top if you want to, then dig in!

The whole mousse cake after it was taken out of the tin.

Here are a few more cake recipes I think you also need to try:

White Chocolate Mousse Cake

5.0 from 5 votes


  • For the cake layer:
  • 90g unsalted butter, softened

  • 90ml vegetable oil

  • 180g granulated sugar

  • 2 teaspoons vanilla extract

  • 3 eggs

  • 180g self raising flour

  • 40ml whole milk

  • For the mousse:
  • 300ml double cream

  • 4 egg whites

  • 1/2 teaspoon cream of tartar

  • 50g granulated sugar

  • 450g white chocolate

  • 4 egg yolks

  • 2 teaspoons vanilla extract

  • 1/4 teaspoon salt


  • Making the cake layer:
  • Start by pre-heating your oven to 180c/350f. Also grease and line an 8 inch cake tin, leave this aside.
  • In a large bowl, add the softened unsalted butter, oil, sugar and vanilla extract. Beat these together on high speed for 5 minutes. If you are making this by hand, just aggressively whisk for as long as you can.
  • Add the eggs into this and whisk. Then add the flour and milk and whisk just until you get a smooth batter.
  • Pour this batter into your cake tin and bake for around 45 minutes, or until a toothpick inserted into the centre comes out clean.
  • Once baked, leave to cool completely.
  • Making the mousse:
  • Pour your double cream into a large bowl. Whip this on high speed until you get firm peaks. Leave this aside.
  • In a separate large bowl, add the egg whites and cream of tartar. Start whipping this, then once the egg whites become foamy, start pouring in the granulated sugar whiles still whipping.
  • Once all the sugar has been added, whip until you get stiff peaks. Leave this aside.
  • In a final large bowl, add the chocolate. Place this into your microwave and heat in 15 seconds intervals, until all the chocolate has melted.
  • Add the egg yolks and whisk these in. This mixture will become super thick, don't worry this is expected.
  • Add a large dollop of your whipped cream into this and whisk this in, to loosen up the mixture. Also at this point whisk in the vanilla and salt.
  • Add in the rest of the whipped cream and gently fold this in.
  • Add half of the whipped egg whites into this, gently fold these in. Now add the remaining whipped egg whites and fold these in until you can no longer see any lumps or streaks of the egg whites.
  • Assembling the cake:
  • Get an 8 inch springform or loose bottom cake tin. Line the bottom and sides of the tin with some baking paper.
  • Add your cooled cake layer into this tin. I cut the top of my cake layer off, just to make it more flat and even, but you don't have to.
  • Add your mousse mixture into the tin and smooth it out. I also added a swirl on top.
  • Leave this in your fridge overnight.
  • The next day, take it out of the tin. I piped some whipped cream on top to decorate, but you don't have to do this.
  • Cut into the cake and enjoy!

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