Ingredients:
- 120 g butter
- 190 g sugar
- 2 eggs
- 270 g of flour
- 5 tablespoons of good quality cocoa powder
- 1 teaspoon of baking powder
- 1/2 teaspoon of salt
- 1 teaspoon of vanilla extract
- 250 ml of buttermilk
- 250 g icing sugar
- 170 g butter
- 2 egg whites
- A pinch of salt
