Ingredients

Step by step

1. Heat the oven to 190°C, fan 170°C, gas 5. Line two 17cm or 18cm sandwich tins with foil or baking parchment.
2. Heat half the milk and half the soft brown sugar together in a saucepan until the sugar has dissolved, then add the chocolate and stir over a low heat until melted. Remove from the heat and leave to cool slightly.
3. Sift the flour, baking powder and cocoa powder together and set aside. Put the butter in a large bowl, add the remaining sugar and beat together until light and fluffy, using an electric mixer. Gradually add the beaten eggs, alternating each addition with a tablespoon of the flour mixture to prevent it splitting.
4. Fold in the rest of the flour, followed by the remaining milk, then add the still-warm chocolate milk. Mix until smooth; it will have a very runny consistency.
5. Divide the mixture between the 2 lined tins and bake for 20–25 minutes, until risen and firm to the touch. Remove from the oven and leave to cool in the tins.
6. Meanwhile, put the cream cheese, icing sugar and vanilla into a bowl and beat slowly with a handheld electric mixer until smooth. Put the butter in a small pan and soften over a very low heat so that it just disintegrates rather than becoming piping hot. With the hand mixer still on a slow speed, gradually pour the melted butter into the cream cheese mixture until it is completely combined, then whisk it briefly at a higher speed. If the butter was too warm, the frosting may be a bit soft and will need chilling slightly before you use it.
7. Turn the cakes out of their tins and sandwich them together with about a quarter of the frosting. Spread a thin layer of frosting over the top and sides to bind any crumbs and then leave to set in the fridge for an hour.
8. Coat with the remaining frosting, smoothing it with a palette knife. Put the melted chocolate in a parchment piping bag and pipe patterns on the cake.