Mary Berry's chocolate birthday cake

Method

1. Preheat the oven to 180C/160C Fan/Gas 4. Grease two 20cm/8in sandwich tins and line with baking paper.

2. To make the cake, place the cocoa and boiling water into a large bowl and mix well to make a paste. Add the remaining cake ingredients and beat with an electric whisk until smooth and an even chocolate colour.

3. Divide the mixture between the prepared tins. Bake for about 25–30 minutes until well risen, shrinking away from the sides of the tin and springy to the touch. Leave for 10 minutes to cool, then carefully remove from the tins and place on a wire rack to cool completely.

4. Meanwhile, to make the ganache, pour the cream into a small saucepan and heat until piping hot. Remove from the heat, add the chocolate pieces and stir until smooth and shiny. Set aside to cool at room temperature until almost set. Divide the ganache into three.

5. Spread the tops of each cake with apricot jam. Sandwich the cakes with a third of the ganache, then spread another third on top. Take a small palette knife and make a pretty swirl pattern on top. Spoon the remaining third into a piping bag, fitted with a rose nozzle. Pipe large rosettes in one corner of the cake.

6. To decorate the cake, place the truffle balls on the top of the rosettes of icing, then arrange the strawberries around them. Using a teaspoon or small piping bag, drizzle the melted chocolate in a zig-zag design over the truffles.