For the batter, first drain the cherries and collect the juice.
Beat the margarine and sugar until frothy. Beat eggs one by one. Mix the flour and baking powder and stir in.
Now spread half of the dough onto a baking sheet lined with baking paper.
Stir in the cocoa and cream under the other half. Then spread this dough on the light one.
Spread the well-drained cherries evenly on the dough.
Bake in an oven preheated to 180 ° C for about 35-40 minutes.
Pour the cherry juice (approx. 400ml) onto the slightly cooled cake. Because let it cool down completely.
For the buttercream, mix the custard powder, sugar and a little milk together. Put the rest of the milk in a saucepan and bring to the boil. Then add the mix and bring to the boil again while stirring. Take off the stove and let it cool down.
Beat the butter at room temperature until frothy and stir in the cold pudding spoon by spoon.
Pour half of the buttercream into a piping bag and spray strips (or other patterns if desired) onto the cooled cake.
Mix the remaining buttercream with cocoa, pour into the piping bag and squirt onto the cake so that it is completely covered with cream.
Store in a cool place until eaten.