Red chocolate marble cake is one of the beautiful cakes I have leant to bake. I made this cake on Valentine’s day for my lovely family.
I love a good marble cake. There’s just something so appealing about the beautifully marbled swirl that appears when you cut off a slice. The flavor is not too rich but still satisfying, and I really appreciate how it gives both the flavors of chocolate and vanilla.
Ganache frosting is optional but a nice touch and helps to keep things moist.

The swirl process is where many people fail with a marble cake, either under-swirling it so it looks dull , or over-swirling it so that it just looks muddy.
Big swirls. Moving across the pan in horizontal direction, plunge the end of the wooden spoon into the batter and make big swirls, moving across the pan in one direction. It should take about three big swirls to make it across the pan. Then, moving back over the swirls, make three swirls in the opposite direction. Be sure you are reaching all the way to the bottom of the pan (without scraping it) and pay attention to corners.

Here is the recipe

RED CHOCOLATE MARBLE CAKE WITH CHOCOLATE GANACHE

INGREDIENTS

unsalted butter, room temperature, plus more for the pan- 1/2 cup
sugar- 1/2 cup
flour- 1 3/4 cups
baking powder- 1 1/2 tsp.
salt- 1/2 tsp
3 large eggs
teaspoons vanilla 1 1/2 tsp
buttermilk- 2/3 cup ( if you don’t have buttermilk, Mix a tbsp. of vinegar in a cup of milk and let it stand for 15 minutes.
cocoa powder-1/3 cup
5-6 drops of red food color

For the ganache frosting:
2/3 cup of heavy cream
6 ounces dark chocolate, chopped

Instructions

•  Preheat the oven to 350°F. Grease and flour the loaf pan.
• Cream the butter and sugar. Using a stand mixer with a paddle attachment, beat the butter and sugar until light lemon-colored and fluffy, about 5 minutes.
• Measure the flour and crack the eggs. While the butter and sugar are creaming, measure out the flour, baking powder, and salt into a small bowl and whisk lightly to combine. Crack the eggs into a bowl and add the vanilla.
• Add the eggs. Scrape down the sides of the bowl with a spatula. Add the eggs, one at a time, beating well in between each addition and scraping the bowl as needed.

• Add the flour and buttermilk, alternating. Add 1/3 of the flour to the batter and beat on low speed just until incorporated. Then add 1/2 of the buttermilk and beat. Add another 1/3 of the flour, and beat, and then the last of the buttermilk and beat. Finally, beat in the last 1/3 of the flour.
• 
• Transfer roughly 1/2 of the batter to a separate bowl. In a small bowl  mix the cocoa powder with 2 tablespoons of hot tap water until smooth. Mix the food color to this mixture and add this red chocolate mixture to the remaining batter. Beat to incorporate.
• Spoon into the prepared pan, Beginning with the vanilla mixture, place four spoonfuls of batter into the pan, spacing them far enough apart . Add the red chocolate batter into the empty spaces to fill the bottom of the pan. Repeat with the second layer, alternating the vanilla and red chocolate batter.
• Swirl. Using the handle of a wooden spoon or some round long object…like I used the back side of a potato scraper, swirl the batter to create a marbled effect.
• 
• Bake the cake. Place in the oven and bake for about 40 minutes, rotating the pan half way through. The cake is done when it has browned slightly and a cake tester comes our clean when inserted into the middle. Cool on a rack for 10 minutes and then unmold and let cool completely
• HOW TO MAKE THE GANACHE
• Bring the cream to a simmer in a small saucepan. Remove from heat, and add chopped chocolate or chocolate chips. Let sit until chocolate is melted and then stir gently to combine. Let cool slightly until ganache has thickened to a pourable consistency.
• Frost. Place the cake on a serving platter. Pour the ganache over the cake and spread lightly as needed. Allow it to drip down the sides here and there. Slice the cake and serve.