There are no lengthy stages to making this impressive three-tiered cake – simply pop all the sponge ingredients into the mixer and you’re away.
Make the sponges. Heat the oven to 180°C/160°C fan/350°F/Gas 4.
Place all the sponge ingredients in the bowl of a stand mixer fitted with the beater attachment and beat until light and fluffy.
Divide the batter equally between the cake tins and smooth each out with a spatula. Bake the cakes for about 15 minutes, or until a skewer inserted into the centres comes out clean.
Allow the cakes to cool in the tins for 5 minutes, then turn them out onto wire racks to cool completely.
Make the icing. Beat the butter and icing sugar in the bowl of a stand mixer fitted with the beater attachment until smooth.
Melt the chocolate in a bowl suspended over a pan of simmering water. Stir until smooth. Allow to cool slightly, then add to the creamed butter and sugar mixture and beat for a further 2–3 minutes to combine.
Place one sponge on a cake stand. Spread with one third of the icing and top with one third of the raspberries, then place another cake on top. Spread with another third of the icing and top with another third of the raspberries.
Top with the final sponge and spread over the remaining icing. Cover the top with raspberries.