I have always been a big fan of marble cakes. They satisfy cravings for both chocolate and vanilla cake, and always please everyone if you need to serve a crowd. They’re also not difficult to make, even though they make for a really beautiful presentation when you slice into them. All you really need to do is add some chocolate – either cocoa powder or melted chocolate – to half of a vanilla cake batter and swirl everything together.
These marble cupcakes work the same way as full sized marble cakes, just in a smaller package. The only drawback to making them this way is that you can’t really swirl them as much as you can swirl a large cake with a large amount of batter. You could try to swirl the batter in the bowl before portioning it out into the cupcake cups, but this generally leads to over-combing the chocolate and vanilla and you don’t end up with a distinct marble pattern. I prefer to measure out the chocolate and vanilla into each cupcake cup, then give the batter a quick single swirl with a knife before baking. Every cupcake ends up with the right amount of chocolate and vanilla this way, and the very distinct black-and-white swirling layers make for a beautiful contrast.
The cake is the same basic recipe that I used for my Rainbow cupcakes, except that instead of dividing it up into many small portions for food coloring, I simply added some melted chocolate to half the batter. One ounce of dark chocolate (semisweet will work, too) adds just the right amount of chocolate flavor to the mix. I used a similar technique on the icing, dividing a basic recipe and adding cocoa powder to half. I put both icings into the same piping bag so that the frosting would have a marble look to it. The wider your pastry tip is, the clearer the effect will be.
1 cup all purpose flour
1 1/2 tsp baking powder
1/4 tsp salt
1/2 cup sugar
2 large eggs
1/2 cup vegetable oil
1/2 cup buttermilk
1 tsp vanilla extract
1-oz semisweet or dark chocolate, melted
Preheat oven to 350F. Grease line 10 cups from a 12 cup muffin tin with paper cups liners.
In a medium bowl, whisk together flour, baking powder and salt.
In a large bowl, whisk together sugar, eggs, vegetable oil, buttermilk and vanilla extract. Pour in dry ingredients and stir until just combined.
Remove 1 cup of the batter to a small bowl and stir in melted chocolate.
Evenly distribute batters into prepared pans, adding a spoonful of vanilla, followed buy a spoonful of chocolate, followed by a little more vanilla. Gently run a knife through the batter to give them a swirl.
Bake for about 15 minutes, until a toothpick inserted into the center comes out clean.
Cool cupcakes on a wire rack before frosting.
Marble Buttercream Frosting
1/2 cup butter, room temperature
3 tbsp milk
1 tsp vanilla extract
approx 2 1/2 cups confectioners’ sugar
2 tbsp cocoa powder
In a large bowl, beat together butter, milk and vanilla. Gradually blend in about 2 cups confectioners sugar until smooth, then divide frosting evenly into two bowls. Blend 2 tbsp cocoa powder into one portion of the frosting and beat until smooth. Add additional confectioners sugar to each bowl as needed, until frosting reaches a thick, spreadable consistency.
Add both colors of frosting to a piping bag, scraping one down each half of the bag to ensure that both colors come out at the same time. Pipe or spread frosting onto cooled cupcakes.