Classic Vanilla-Chocolate Marble Cake

Directions

1. 1

   Preheat your oven to 350 °F (180 °C). Grease and flour a 9-inch (24 cm) round cake pan, tapping out any excess flour.

2. 2

   In a large bowl, beat the softened butter and sugar together until light, pale, and fluffy. Add the egg yolks one at a time, beating well after each addition, then mix in the vanilla extract.

3. 3

   Gradually fold in the sifted flour in three additions, alternating with the lukewarm milk, stirring gently with a spatula until a smooth, lump-free batter forms.

4. 4

   In a spotlessly clean bowl, whisk the egg whites with the salt until stiff peaks form. Fold the baking powder into the whites, then gently incorporate them into the main batter using slow, sweeping motions to keep it airy.

5. 5

   Divide the batter evenly between two bowls. Stir the cocoa powder into one portion, mixing until the color is fully uniform and no streaks remain.

6. 6

   Pour the vanilla batter into the prepared pan, filling about two-thirds. Spoon the chocolate batter on top, then use a fork or skewer to draw swirling spirals through both layers to create the marble effect.

7. 7

   Bake for 35–40 minutes, or until a toothpick inserted in the center comes out clean. Cool in the pan for 10 minutes, then turn out onto a wire rack to finish cooling.