One-bowl chocolate cake with mocha icing

Ingredients

• 1 1/2 cup self-raising flour
• 3/4 cup baking cocoa
• 1 1/2 teaspoon bicarbonate of soda
• 3/4 teaspoon baking powder
• 1 cup brown sugar
• 3/4 cup warm water
• 1/2 cup light sour cream
• 2 beaten eggs
• 90 gram melted butter
• 1 teaspoon vanilla extract
• 300 millilitre thickened cream, whipped
• Mocha icing
• 3 cup sifted icing sugar
• 1/6 cup sifted cocoa
• 3 teaspoon instant coffee powder
• 25 gram melted butter
• 5 tablespoon hot water