Vanilla and Cocoa Sponge Cake - My Greek Dish

Ingredients

• 1 cup butter
• 1 cup sugar
• 5 eggs
• 1 tsp vanilla extract
• 1 pinch of salt
• 2 cups self raising flour
• 4 tablespoons of unsweetened cocoa
• 6 tablespoons milk
• 2 cups icing sugar
• 2 tbsps water
• 1/2 tsp vanilla extract