# What You'll Need:
→ Confetti cake
01 - 2 1/2 cups all-purpose flour
02 - 2 1/2 teaspoons baking powder
03 - 1/2 teaspoon fine salt
04 - 3/4 cup unsalted butter, room temperature
05 - 1 3/4 cups granulated sugar
06 - 4 large eggs, room temperature
07 - 1 tablespoon vanilla extract
08 - 1 cup whole milk, room temperature
09 - 1/2 cup rainbow jimmies-style sprinkles
→ Champagne frosting
10 - 1 cup unsalted butter, room temperature
11 - 4 cups powdered sugar, sifted
12 - 1/4 cup champagne or good-quality sparkling wine, room temperature
13 - 1/2 teaspoon vanilla extract
14 - Pinch of fine salt
→ Decoration
15 - Additional rainbow sprinkles, as needed
16 - Edible glitter or sugar pearls, optional
# How to Make It:
01 - Preheat oven to 350°F. Grease two 9-inch round cake pans, line the bottoms with parchment paper, and grease the parchment.
02 - Whisk the all-purpose flour, baking powder, and salt together in a medium bowl until evenly distributed; set aside.
03 - Using a stand mixer fitted with the paddle or an electric hand mixer, beat the unsalted butter and granulated sugar on medium-high speed until pale and fluffy, about 3 minutes.
04 - Add the eggs one at a time, mixing well after each addition, then beat in the vanilla extract until fully combined.
05 - With the mixer on low, add the flour mixture to the batter in three additions, alternating with the milk and beginning and ending with the flour; mix just until combined.
06 - Use a rubber spatula to gently fold in the rainbow jimmies, taking care not to overmix to prevent color bleed.
07 - Divide the batter evenly between the prepared pans and smooth the tops with an offset spatula or the back of a spoon.
08 - Bake for 28–32 minutes, or until a toothpick inserted into the center comes out clean. Cool the cakes in the pans for 10 minutes, then turn them out onto cooling racks to cool completely.
09 - Beat the butter until creamy. Gradually add the sifted powdered sugar, 1 cup at a time, mixing on low speed. Add the champagne, vanilla, and a pinch of salt, then beat on medium-high until the frosting is light and fluffy, 3–4 minutes.
10 - Place one cake layer on the serving plate or cake stand, spread an even layer of buttercream, set the second layer on top, then frost the top and sides with the remaining buttercream.
11 - Finish by pressing additional sprinkles onto the sides and top and adding edible glitter or sugar pearls as desired. Chill briefly to set the buttercream before serving if needed.
