Confetti Birthday Cake

In the bowl of a stand mixer fitted with a paddle attachment, cream the butter and the sugar until fluffy and light in color, about 3 minutes. With the mixer running on low, slowly stream in the oil. Scrape the bottom and sides of the bowl with a rubber spatula and beat for one additional minute.

Add in the eggs and egg whites one at a time, followed by the vanilla, and cake batter extract, combining well after each addition and scraping the bowl as needed.

Sift together the cake flour, baking powder, baking soda, and salt. Add half of the flour mixture and the sour cream to the bowl. With the mixer running on low speed, slowly stream in about half the buttermilk. Mix just until combined then scrape the bow. Add the remaining flour and slowly stream in the remaining buttermilk with the mixer running on low speed until combined. Fold in the sprinkles until fully incorporated.

Evenly divide the batter among the prepared cake pans (I like to use a scale to weigh the batter into each pan). Bake for 25-30 minutes, until the center of the cakes spring back to the touch (or a toothpick comes out with a few moist crumbs.

Allow the cakes to cool in the pans for at least 30 minutes then run a small spatula around the sides of the pan to help release the cakes. Flip the cakes onto a wire rack to finish cooling.

Chocolate Cream Cheese Frosting: Using a stand or hand mixer, cream the butter and cream cheese until smooth, about 2 minutes. Scrape down the bowl with a rubber spatula.

Sift together the powdered sugar and cocoa powder. Add half the powdered sugar and cocoa, followed by the heavy cream, vanilla, and salt. Mix on low until mostly incorporated then add the remaining half of powdered sugar and cocoa. Scrape the bowl again then mix until the frosting is combined and smooth.

Assemble & Decorate: Once the cakes are completely cool, use a large serrated knife to slice off the tops of each cake layer to create a flat surface.

Place the first cake layer, cut side up, on a cake board or stand. Add about ½ cup of frosting and spread it out to the edges. Place your next cake layer cut side down on top and gently press down. Repeat the same process with another ½ cup frosting and for the the final cake layer, place it cut side down.

Coat the top and sides of the cake with a thin even crumb coat of frosting using an offset metal spatula and a straight-sided icing comb. Chill the cake in the fridge for at least 30 minutes.

Spread a final layer of frosting all over the cake and decorate with sprinkles. Fit a piping bag with a star tip and fill it with the leftover frosting and pipe rosettes on the top of the cake. Slice up and enjoy!