Yellow Cake with Chocolate Frosting

1. Preheat the Oven

Begin by preheating your oven to 350°F. Meanwhile, prepare three 9-inch cake pans by greasing them with nonstick cooking spray or softened butter.

2. Mix the Dry Ingredients

In a large bowl, whisk together the all-purpose flour, baking powder, kosher salt, and baking soda. Set the bowl aside.

3. Combine the Wet Ingredients

In a medium bowl or measuring cup, combine the buttermilk, vegetable oil, and vanilla extract. Stir these ingredients together and set aside.

4. Cream the Butter and Sugars

In a large bowl, beat the unsalted butter at room temperature with the granulated sugar and light brown sugar until light and fluffy, about 4 minutes.

5. Incorporate the Eggs

Add the eggs and egg yolks to the creamed butter mixture, one at a time, allowing each to blend fully before adding the next, for about 5 minutes.

6. Blend the Dry and Wet Mixtures

Gradually add the flour mixture and the buttermilk mixture to the batter, alternating between the two and starting and ending with the flour mixture, until well blended and no lumps remain.

7. Bake the Cake Layers

Divide the batter evenly among the prepared cake pans. Bake for 35-40 minutes, rotating the pans halfway through, until golden brown and tops spring back when gently pressed.

8. Cool the Cakes

Allow the cakes to cool in their pans for about 5 minutes before transferring them to a wire rack to cool completely.

9. Prepare the Chocolate Frosting

Melt the bittersweet chocolate. In a large bowl, beat the unsalted butter until fluffy. Gradually add the confectioners’ sugar and a pinch of kosher salt. Incorporate the sour cream, then blend in the melted chocolate until smooth and creamy.

10. Assemble the Cake

Place one cake layer on a serving plate, spread a layer of frosting on top, and repeat with remaining layers. Cover the top and sides of the cake with frosting and decorate as desired.