This is the cake I imagined Kate making in The Disengagement Ring (minus a certain magic ingredient that gets added later). The cake itself is a baked mousse and has no flour in it, and the filling is also mousse, so it’s all very light. And if you believe that … well, you’ll be surprised how rich this cake is. It’s exceptionally good served with vanilla ice-cream.

I’m sure you all know the drill when making chocolate cake – use good quality chocolate with at least 70% cocoa solids. It’s quite an expensive cake to make because of all the chocolate, but a little does go a long way.




225g plain chocolate

5 eggs, separated

150g caster sugar

12g softened butter

60ml orange-flavour liqueur (optional)

Mousse filling

142ml double cream

225g plain chocolate

4 eggs, separated

To finish

Cocoa powder/Flake or other decoration of your choosing


Grease an 8-inch cake tin. Melt the chocolate in a bowl over a pot of simmering water.

Put the egg yolks and caster sugar in a bowl over a pot of simmering water and whisk together for about 3 minutes until thick and creamy. Continue whisking and add the softened butter a little at a time, then whisk in the melted chocolate.

Whisk the egg whites to soft peak stage, then fold into the chocolate mixture with a metal spoon. Pour the mixture into the cake tin and cook at 180°C (350°F/gas mark 4) for 50 minutes or until the cake has risen and the top is beginning to crack.

Leave the cake to cool in the tin for 1 hour. It will sink at this stage. The recipe I have says not to worry, but I always do and it still turns out fine. So panic is optional.

Remove the cake from the tin and cut it in half horizontally. Put the top half, cut side up, back in the tin and drizzle over half the liqueur if you’re using it. I tend to make a shambles of cutting it, but you can do a bit of patchwork here on the bottom half. Make sure to keep the best half for the top. Drizzle the remaining liqueur over the bottom half and set aside.

Mousse filling

Lightly whip the cream. Melt the chocolate and allow it to cool a little, then beat in the egg yolks. Fold in the whipped cream. Whisk the egg whites to soft peak stage, then fold into the chocolate mixture with a metal spoon. Spoon the mousse over the cake half in the tin, spreading it out to the edges. Then chill for 3 hours or overnight.

Top with the remaining cake half, cut side down. Remove the cake carefully from the tin and smooth the edges with a palette knife.

You can dust the top with cocoa powder if you like and make a chocolate collar to go around the cake. But I just covered the top and sides in crushed Flake.