Marble cake in coffee buttercream frosting

It's my cell group Christmas get-together on 8 Jan 2011. Decided to bake a marble cake with silk meringue coffee buttercream frosting. The texture is lighter than just pure buttercream due to the addition of stiffly beaten egg whites. It is worth the extra effort put in as it definitely tasted better. I also thought that buttercream will be easier to frost and decorate than fresh cream.  But not really due to our hot weather. So you can see the imperfections in my frosting in the pictures below. Need more practice in a cool room next time. Didn't have the chance to take a picture of a slice to see the marbled pattern in the cake.

Ingredients:

12g cocoa powder
24g hot water
2 large eggs
2 large egg yolks
45g milk
55g heavy cream
¾ tsp vanilla essence
150g cake flour, sifted
113g sugar
1½ tsp baking powder
½ tsp salt
134g unsalted butter, softened


Preparation:
Preheat oven at 170°C.
Grease and flour a 7” x 3” round cake tin. Line the base with parchment paper.

Method:
1. Dissolve the cocoa powder into the hot water and mix well. Leave it aside to cool.
2. In a medium bowl, lightly combine all the eggs, ¼ cup each of the milk and heavy cream and vanilla essence.
3. Combine flour, sugar, baking powder and salt into the mixing bowl and mix on low speed for 30 seconds to blend.
4. Add the butter and ¾ cup each of the remaining milk and heavy cream into the above mixture. Mix on low speed until the dry ingredients are moistened.
5. Increase speed to medium (high speed if using hand mixer) and beat for 1.5 minutes to aerate and develop the cake’s structure. Scrape down the sides of the bowl.
6. Gradually add the egg mixture in 3 batches into the mixing bowl, beating for 20 seconds after each addition to incorporate the ingredients and strengthen the structure. Scrap down the sides.
7. Remove about 1/3 cup of the batter above and mix into the cooled chocolate mixture. Blend well.
8. Pour ½ of the non-chocolate mixture into the cake tin followed by all the chocolate mixture and lastly, followed by the remaining non-chocolate mixture. The pan will be about half full.
9. Smooth the surface with a spatula. Use a tablespoon to gently swirl the batter to create the marble pattern.
10. Bake for 25-35min or until a tester inserted near the centre comes out clean and the cake springs back slightly when pressed lightly in the centre.
11. Remove from oven and rest the cake in the cake tin in a wire rack for 10 minutes before unmoulding.