Vanilla Orange And Chocolate Marble Cake

Preheat the oven to 180C. Lightly grease and line a 20 cm cake tin.

Cream the butter, sugar, vanilla essence and orange zest until light and fluffy. Add the eggs, a little at a time until well combined. Fold in the sifted flour.

Remove half of the mixture to a separate bowl. Stir in the chocolate until well combined.

Drop spoonfuls of the mixtures alternately into the lined tin. Bake for 35 minutes, or until a skewer comes out clean. Cool in the tin for 10 minutes before turning out onto a wire rack.

Mix together icing ingredients, adding enough boiling water to reach desired consistency. Spread over cake and serve.