# What You'll Need:
→ Cakes
01 - 2 1/2 cups all-purpose flour
02 - 2 1/2 teaspoons baking powder
03 - 1/2 teaspoon fine salt
04 - 1 cup unsalted butter, room temperature
05 - 2 cups granulated sugar
06 - 4 large eggs, room temperature
07 - 1 tablespoon pure vanilla extract
08 - 1 cup whole milk, room temperature
09 - 1/4 cup instant vanilla pudding powder (optional)
10 - Yellow gel food coloring, as needed
→ Frosting
11 - 1 1/2 cups unsalted butter, room temperature
12 - 5 cups powdered sugar, sifted
13 - 2 teaspoons pure vanilla extract
14 - 2 to 3 tablespoons whole milk or heavy cream
15 - Pinch of fine salt
# How to Prepare:
01 - Preheat oven to 350°F. Grease two 9-inch round pans and line the bottoms with parchment; set aside.
02 - Whisk together the all-purpose flour, baking powder and salt in a medium bowl until evenly distributed; set aside.
03 - Using an electric mixer, beat the softened butter with the granulated sugar on medium-high speed until pale and fluffy, about 3 to 4 minutes.
04 - Add the eggs one at a time, beating well after each addition, then mix in the vanilla extract until homogeneous.
05 - Add the dry mixture to the butter mixture in three additions, alternating with the milk and beginning and ending with the dry ingredients; mix just until combined to avoid overworking the batter. If using, whisk in the instant vanilla pudding powder with the dry ingredients before adding.
06 - Portion the batter evenly between two bowls. Add a small amount of yellow gel to one bowl and stir until the desired shade is reached.
07 - Using separate spoons, dollop alternating spoonfuls of the yellow and uncolored batters into the prepared pans. Once filled, run a skewer or knife through the batter in wide figure-eight motions to create a gentle marble effect.
08 - Bake in the preheated oven for 30 to 35 minutes, rotating the pans once if necessary, until a toothpick inserted into the center comes out clean or with a few moist crumbs.
09 - Allow the cakes to cool in their pans on a rack for 10 minutes, then invert onto a cooling rack and remove the parchment. Cool completely before assembling.
10 - Beat the softened butter until smooth and creamy. Gradually add the sifted powdered sugar, beating on low then increasing speed. Add the vanilla, salt and 2 tablespoons of milk or cream; add more liquid as needed to reach a spreadable consistency.
11 - If necessary, level the cake tops with a serrated knife. Place one layer on a serving plate, spread an even layer of frosting, then top with the second layer.
12 - Frost the top and sides with the remaining buttercream using an offset spatula. Decorate as desired, allowing the finished cake to rest briefly to set the frosting before slicing.
