Marble Cake

Method

19 steps

1. 1

   Marble Cake:

2. 2

   Preheat your oven to 350F. Butter 2 (8" or 9") round cake pans and line the bottoms with parchment paper. Lightly dust the sides of the pans with flour and tap out any excess. Set aside.

3. 3

   In a medium bowl, whisk together flour, cornstarch, baking powder, baking soda, and salt. Set aside.

4. 4

   In a large measuring cup, mix together milk and vinegar. Set aside for 5 minutes while you prep the rest of the batter. It will thicken and curdle slightly.

5. 5

   In a large bowl, combine butter, oil, and sugar. Using an electric mixer fitted with the paddle attachment or a wooden spoon by hand, cream together until lump free. It will look a little grainy but you shouldn't see any lumps of butter.

6. 6

   Whisk the eggs in, one at a time, mixing well after each addition. Whisk in the vanilla with the final egg.

7. 7

   Alternate mixing in the dry ingredients and milk. Start with about 1/3 dry ingredients followed by half of the milk. Mix in another 1/3 of dry ingredients, the remaining milk, and then finish off with the final 1/3 of the dry ingredients.

8. 8

   In a separate medium bowl, whisk together unsweetened and black cocoa powder and the 5 additional tablespoons milk until smooth.

9. 9

   Pour about half of the plain vanilla cake batter into the bowl with the cocoa mixture and fold together until streak free.

10. 10

    Using a large cookie scoop or spoon, drop alternating dollops of the vanilla and chocolate cake batters into your baking pans (see above post for visual). You should have a blobby pattern that kind of looks like a chess board.

11. 11

    Run a skewer or butter knife up and down through the batters to lightly swirl them and create the marble effect.

12. 12

    Bake the cakes in the center of your preheated oven for 30-35 minutes (for 8" cakes) or 25-30 minutes (for 9") or until a skewer inserted into the center comes out clean with a few moist crumbs.

13. 13

    Cool the cakes for 10 minutes in the baking pans then flip onto a wire rack. Set aside to cool completely to room temperature before frosting.

    Chocolate Buttercream:

14. 14

    In a large bowl, combine butter and powdered sugar.

15. 15

    Using an electric mixer fitted with the paddle attachment, mix together on low speed until the sugar is dissolved.

16. 16

    Add in the cocoa, salt, 3 tablespoons milk, and vanilla.

17. 17

    Mix again on low until combined then increase the mixer speed to high and whip for about 1 minute or until smooth and fluffy.

18. 18

    If the frosting is too thick, mix in more milk, 1 tablespoon at a time, until it reaches your desired consistency.

19. 19

    Lay a cooled cake on a turntable or cake stand and spread some frosting on top. Place the second cake layer on top then use the remaining frosting to cover the outside.