Ingredients

Step by step

1. Preheat your oven to 180°C, fan 160°C, gas 4. Lightly butter the sides of a 22cm round springform cake tin, then line the base with a disc of baking paper. Put the butter and chocolate into a large heatproof bowl and place over a pan of barely simmering water, ensuring the water doesn't touch the bowl. Heat gently, stirring regularly, until melted. Remove from the heat and cool slightly for about 5 minutes.
2. In a very clean grease-free bowl, whisk the egg whites until they reach the soft peak stage. When you lift out the whisk, the fluffy whites should stand to a peak with the tip just curling over. Now, while whisking continuously, gradually add 100g sugar a little at a time over a period of 3-4 minutes, until incorporated. Then whisk for a couple more minutes until thick and glossy.
3. In a separate large mixing bowl, whisk the egg yolks together with the remaining sugar, until light and fluffy. Add the cooled chocolate mixture, folding gently so as not to knock out too much air. Once combined, lightly fold in half the egg whites. Continue to fold in the remaining whites, then pour half the mixture into the prepared cake tin. Reserve the remaining mousse, cover and set aside in the fridge.
4. Bake on the middle shelf of the oven for 25-30 minutes until a metal skewer inserted into the centre comes out clean. Remove the cake from the oven; allow it to cool in the tin. Don't panic when it sinks as it cools.
5. Once completely cold, spoon the remaining mousse on top and spread out smoothly with a palette knife. Dip the palette knife in hot water for a smooth surface. Transfer to the fridge to set for at least 2-3 hours.
6. Remove the cake from its tin and smooth down the sides with a hot palette knife.
7. Just before serving, dust the top with sifted cocoa and top with the strawberries.
   Tip

   This recipe contains raw egg