1. Stand 24 paper cake cases in the holes cake trays and pre-heat the oven.

2. Put the sponge mix into a mixing bowl, add the cocoa and stir to combine.

3. Break the eggs into the bowl, add the oil and water and beat everything together until smooth.

4. Divide the mixture between the prepared cake cases.

5. Bake the cakes for 18-20 minutes, until the sponge springs back when touched.

6. Transfer the cakes to a wire rack and leave to cool.

Topping

1. Sieve the icing sugar and cocoa into a mixing bowl and stir to combine.

2. Add the softened butter and mix to a smooth paste.

3. Pipe or spread the paste over the cold cakes.

4. Place some mini chocolate eggs or smarties on top for decoration.