Chocolate Mousse Cake

Step 1: Whisk eggs and half the sugar until pale in color and thick in texture.

Step 2: Gently heat the remaining sugar in a small pan with the water,stirring until dissolved. Remove from heat,add butter and chocolate. Stir until mixture is melted. Beat the chocolate mixture into the egg mousse for no more than 1 minute.

Step 3: Pour into a greased 20cm sponge sandwich pan, which has had the bottom and sides lined with baking paper, so it stands about 2cm above the rim of the pan. (Or use a smaller pan if you ant a deeper slice). Sit in a roasting dish and pour in freshly boiled water until it reaches just below the rim of the pan.

Step 4: Bake in a preheated moderately slow oven for 40 minutes or until set. The top will feel firm when you place the flat of your hand gently on top of the cake. Cool and chill overnight in the pan.

Step 5: To serve, bring the cake to room temperature and turn out onto a plate and dust with the cocoa powder just before serving.

Step 6: When slicing use a hot knife dipped in water.