Step by step

Method

11 steps

1. 1

   Prepare the Pan: Preheat the oven to 350°F (175°C). Grease a 9-inch round cake pan and line the bottom with parchment paper.

2. 2

   Cream the Butter and Sugar: Beat the softened butter and granulated sugar until pale, creamy, and fluffy. This usually takes a few minutes and helps create a lighter cake texture.

3. 3

   Add the Eggs and Vanilla: Add the eggs one at a time, mixing well after each addition. Add the vanilla extract and mix until combined.

4. 4

   Combine the Dry Ingredients: In a separate bowl, whisk together the all-purpose flour, baking powder, and salt.

5. 5

   Make the Vanilla Batter: Gradually add the dry ingredients to the butter mixture, alternating with the whole milk and sour cream. Mix just until combined. Do not overmix.

6. 6

   Make the Chocolate Batter: Transfer about one-third of the vanilla batter to a separate bowl. Add the unsweetened cocoa powder and gently mix until smooth.

7. 7

   Add the Batters to the Pan: Spoon alternating portions of vanilla and chocolate batter into the prepared cake pan. Spread gently so the batter is distributed evenly.

8. 8

   Create the Marble Effect: Use a butter knife or wooden skewer to gently swirl the two batters together. Make only a few passes to keep the chocolate and vanilla patterns distinct.

9. 9

   Bake: Bake for approximately 40–45 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs.

10. 10

    Cool: Let the cake cool in the pan for about 10 minutes. Transfer it to a wire rack and allow it to cool completely.

11. 11

    Slice and Serve: Once cooled, slice the marble cake and serve. Enjoy it plain, with powdered sugar, whipped cream, fresh berries, or a chocolate glaze.