• Preheat the oven to 350℉. Line three 8-inch cake pan with baking spray. Line the bottoms with parchment paper circles and spray again. Set aside.
• In a medium bowl sift the flour, baking powder, baking soda, and salt.
  3 1/2 cups Cake flour, 1 tsp Baking powder, 1/2 tsp Baking soda, 1 tsp Salt
• Using a mixer in a large bowl, beat the butter, oil, and sugar on high speed for 2 minutes. It will become white in color and fluffy.
  3/4 cup Unsalted butter, 1/4 cup Oil, 1 3/4 cups White granulated sugar
• Add in the eggs, egg yolks, vanilla, and sour cream. Mix on medium until combined.
  3 Large eggs, 2 Egg yolks, 1 tsp Pure vanilla extract, 1/4 cup Sour cream
• Add the dry ingredients and buttermilk and mix on low speed until just combined. Split the batter evenly between the cake pans.
  1 cup Buttermilk
• Bake for 26-29 minutes until toothpick inserted comes out clean.
• Let the cakes sit in the hot pans for 10 minutes before transferring to a cooling rack. Cool completely before decorating.

Chocolate Cream Cheese Frosting

• In a large bowl, sift the powdered sugar and cocoa powder together. Set aside.
  3 cups Powdered sugar, 3/4 cup Unsweetened cocoa powder
• Using a mixer, beat the butter on high speed for 2 minutes. Scrape the bowl and add the cream cheese. Beat on high for 1 minute.
  1 1/2 cups Unsalted butter, 8 oz Cream cheese
• Add in half of the powdered sugar and mix on low speed. Add in the rest of the powdered sugar and mix on low until combined. Add in the vanilla and mix on high speed until creamy.
  1 tsp Pure vanilla extract

Assembly

• Use a serrated knife to cut the domes off the top of the cakes. Place the first cake layer down.
• Spread 1 cup of frosting over the cake. Repeat with the second cake layer. Place the third cake layer with the bottom of the cake facing up.
• Frost the cake in a light layer of frosting and freeze for 15 minutes. Then, frost the rest of the cake. Optional: I used Wilton 6B to pipe decoration on the top. Then top with sprinkles.
  Sprinkles