Treat yourself to this silky chocolate mousse cake, then check out more indulgent chocolate recipes such as our chocolate mousse, ultimate chocolate fudge cake, moist chocolate cake and chocolate brownies.

We've also got plenty more indulgent chocolate mousse recipes to try, including classic chocolate mousse, vegan chocolate mousse, white chocolate mousse and avocado chocolate mousse.


  • 1 tbsp dark rum, (optional)
  • salted pretzels, crunched to serve


  • 50g plain flour
  • 2 tbsp cocoa powder
  • 1/4 tsp baking powder
  • 1/4 tsp bicarbonate of soba
  • 55g light soft brown sugar
  • 2 tbsp malted milk powder (Horlicks)
  • 50g smooth biscuit spread
  • vegetable oil
  • 80ml buttermilk
  • 1/2 tsp vanilla extract
  • 1 small egg


  • 300g milk chocolate, broken into chunks
  • 450g double cream


  • 100ml double cream
  • 100g milk chocolate, broken into chunks
  • 2 tbsp unsalted butter


  • STEP 1

    Heat the oven to 180C/fan 160C/gas 4. Oil a 20cm springform cake tin and line the sides and base with baking paper, making sure the paper comes a little higher than the sides of the tin.

  • STEP 2

    Sieve the flour, cocoa, baking powder, and bicarb into a bowl. Add the sugar, a pinch of salt and the Horlicks. Mix the biscuit spread, 1 tbsp vegetable oil, buttermilk, vanilla and egg in a jug, then pour into the bowl. Beat well until smooth, then pour into the tin (it will only come about 2cm up the tin). Bake for 20-25 minutes until risen and a metal skewer comes out clean when poked into the centre of the cake. Leave to cool in the tin. Brush with the rum (if using) while the sponge is just warm, then leave to cool to room temperature.

  • STEP 3

    For the mousse, melt the chocolate in a bowl over (but not touching) simmering water (or in a microwave in short blasts), then leave to cool. Whip the cream in a large bowl until you get soft peaks, then fold in the cooled melted chocolate very gently trying not to knock any air out.

  • STEP 4

    Spoon the mousse over the cooled cake in the tin, and smooth the top. Chill for at least 4 hours until the mousse has set.

  • STEP 5

    For the ganache, heat the cream in a pan until hand-hot. Remove from the heat and add the chocolate and butter. Stir until the chocolate has melted, then tip into a bowl. Leave to cool to room temperature. When the mousse has set, pour/spread the cooled ganache over the cake and cool for another 2 hours to set, or overnight if making it the day before.

  • STEP 6

    To serve, remove from the tin, transfer to a serving plate, and gently pull away the baking paper around the sides of the cake. Use a warm knife to cut slices of the cake, and serve scattered with the pretzel pieces over the top.

To serve, dip the knife into hot water, and then dry with a tea towel before cutting into the cake. This ensures a clean cut through the cake. Repeat before slicing the next piece.

For tips on melting chocolate, search, and listen to episode #23 of the olive magazine podcast.

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