A classic marble cake with swirls of red and blue colors, combining vanilla and buttermilk flavors.

Scale

Preheat oven to 350 F. Grease and flour a 12-cup Bundt pan. Set aside.
In the bowl of a stand mixer fitted with a paddle attachment (or with an electric mixer), beat together butter and sugar until well-combined.
Add eggs and egg whites one at time, mixing well after each addition.
Stir in vanilla until combined.
Mix in buttermilk until well-combined.
Add cake flour, baking powder, and salt.
Stir in on low just until incorporated.
For the red swirl, scoop out 1 ½ cups of the batter and place it into a separate bowl.
For the blue swirl, scoop out an additional 1 ½ cups of batter and place it into a third bowl.
Mix in the red food coloring into plain batter that you scooped out.
Mix the blue food coloring into the other bowl of plain batter that you scooped out.
Using a 1/4-cup measuring cup, drop one scoop of plain batter into prepared bundt pan.
Using a separate scoop, drop 1/4 cup of red batter on top of plain batter.
Using a third scoop, drop 1/4 cup of blue batter on top of the red batter.
Continue to alternate between plain and colored batters until all three batters are gone.
Give the pan a couple of taps to level out the batter, if necessary. Do not stir.
Bake for 50-70 minutes, or until a wooden toothpick inserted into the center comes out clean.
Cool cake in the pan on a wire rack for 15 minutes.
Invert the cake onto wire rack, and cool completely.

Keywords: marble cake, bundt cake, dessert, baking