Ingredients
Cake
- 2½ cups (300 g) all-purpose flour
- 2½ tsp baking powder
- ½ tsp salt
- ¾ cup (170 g) unsalted butter, softened
- 1½ cups (300 g) granulated sugar
- 4 large eggs, room temperature
- 2 tsp vanilla extract
- 1 cup (240 ml) whole milk, room temperature
- ¾ cup (120 g) rainbow jimmies sprinkles
Vanilla frosting
- 1 cup (227 g) unsalted butter, softened
- 4 cups (480 g) powdered sugar
- 2 tsp vanilla extract
- 2–4 tbsp milk or heavy cream
- Pinch of salt
- Extra sprinkles, for decorating
Instructions
- Prep: Heat oven to 350°F (175°C). Grease and line two 8-inch round cake pans with parchment.
- Combine dry ingredients: Whisk together flour, baking powder, and salt.
- Cream butter and sugar: Beat butter and sugar for about 3–4 minutes, until light and fluffy.
- Add eggs and vanilla: Beat in the eggs one at a time, then mix in vanilla.
- Add milk and flour: Mix the dry ingredients into the batter in 3 additions, alternating with the milk. Mix just until combined—don’t overmix.
- Fold in sprinkles: Gently fold in the jimmies by hand. Avoid nonpareils, which can bleed their color into the batter.
- Bake: Divide batter between pans and bake for 25–30 minutes, or until a toothpick inserted in the center comes out clean.
- Cool: Let cakes cool in the pans for 10 minutes, then transfer to a rack and cool completely.
- Make frosting: Beat butter until creamy. Gradually add powdered sugar, then vanilla, salt, and enough milk or cream to reach a smooth, spreadable consistency.
- Assemble: Place one cake layer on a plate, spread with frosting, add the second layer, and frost the top and sides. Finish with plenty of sprinkles.