200g unsalted butter, softened, plus extra for the tin
200g golden caster sugar
4 tbsp cocoa powder
200g self-raising flour
1 tsp baking powder
1-2 tbsp whole milk
200g unsalted butter, softened
400g icing sugar
4 tbsp cocoa powder
CHOCOLATE DRIP GANACHE
100g dark chocolate, finely chopped
200ml double cream
Heat the oven to 180C/fan 160C/gas 4 and butter and line 2 x 20cm loose-bottomed cake tins. Put the butter and sugar into a bowl and use electric beaters to whisk until light and fluffy. Whisk in the eggs, one at a time, alternating with a tbsp of the cocoa powder between each addition.
Tip in the flour and baking powder with a pinch of salt and whisk briefly to a smooth batter. If the batter is a little stiff, and fails to drop from a spoon, beat in 1-2 tbsp of milk. Scrape into the two cake tins and bake for 20-22 minutes or until risen and firm. Cool in the tins.
To make the buttercream, put the butter into a bowl and use electric beaters to whisk until really light and fluffy. Mix the icing sugar and cocoa powder together, then whisk into the butter a spoonful at a time until you have a light, fluffy buttercream. Add 1-2 tbsp of just-boiled water if it’s a little thick.
Put one of the sponges onto a cake plate or stand and spread with a thick layer of icing, then sandwich the other sponge on top. Ice the top of the sponge with another thick layer of icing, then use the remaining icing to cover the sides of the cake in an even layer. Chill the cake for 30 minutes.
Make the chocolate drip ganache by putting the chocolate into a bowl and pouring the cream into a small pan. Heat the cream until almost simmering before pouring it over the chocolate. Leave to sit for 1 minute, then stir to a smooth, thin ganache. Transfer to a squeezy bottle with a thin nozzle or a jug with a lip. Leave to cool slightly.
Remove the cake from the fridge and pour some of the glaze onto the top of the cake to cover.
Use the lip of the jug or squeezy bottle to tease some of the ganache gently down the sides of the cake, to create drips.
The ganache will set hard on the cold cake. Cut into slices to serve.