1 Preheat the oven to 180°C/fan 160°C/gas mark 4. Grease and line with greaseproof paper the sides of two cake tins roughly a 20cm tin.
2 Blend the cocoa and boiling water in a large bowl. Add the remaining sponge ingredients and beat until the mixture has become a smooth, thickish batter. This can be easily done with an electric hand whisk. Divide the cake mix equally between the prepared tins and level the surface.
3 Bake in the pre-heated oven for about 25-30 minutes or until well risen and a skewer inserted into the cetnre comes out clean. Leave to cool in the tins for a few minutes before turning out. Peel off the parchment and finish cooling on a wire rack.
4 To make the icing, melt the chocolate gently in a bowl set over a pan of hot water, stirring occasionally. Add the butter and stir until the icing has the consistency of thick pouring cream.
5 Stand the wire rack on a baking tray to catch any drips. Sandwich the cakes together with icing in the middle and use a small palette knife to smooth the icing over the top of the cake.
6 Allow to time for the icing to cool and set. Decorate how you desire. Keep in a cool place until ready to serve.
I've grown up with this being our favourite family birthday cake recipe
A popular birthday cake in my house for its delicious chocolately richness
An indulgent treat that seems to disappear very quickly in my house
The white chocolate equivalent of a brownie – light and fluffy with the added crunch of pecans
A super speedy recipe that gets eaten up as quickly as the time it takes for you to make them