225g butter, softened
225g caster sugar
4 eggs
225g self-raising flour
3 tbsp milk
1 tsp vanilla extract
2 tbsp cocoa powder
Heat the oven to 180C. Grease a 20cm cake tin and line the bottom with parchment paper.
Put butter, caster sugar, 4 eggs, self-raising flour, 3 tbsp milk, and vanilla extract in a food processor or electric mixer and whisk for 1-2 minutes until smooth.
Divide the mixture into 2 parts and stir the cocoa powder in one part for the cocoa batter. Take 2 tbsp from each batter and dollop into the greased tin alternately.
Create swirl patterns with a skewer or knife and smoothen out the top.
Bake the cake for 45-55 minutes and check doneness by inserting a toothpick. Take the cake out and leave it to cool. Serve it right away and enjoy.