Ingredients:

  • 2.25 cups (280g) all-purpose flour
  • 1.5 cups (300g) granulated sugar
  • 3.5 tsp (17g) baking powder
  • 1 tsp (5g) salt
  • 0.75 cup (170g) unsalted butter, softened
  • 1 cup (240ml) whole milk, room temperature
  • 1 tbsp (12ml) vanilla extract
  • 3 large eggs, room temperature
  • 1 cup (225g) unsalted butter, softened
  • 4 cups (500g) powdered sugar, sifted
  • 2 tbsp (30ml) heavy cream
  • 1 tsp (5ml) vanilla extract
  • 0.5 cup (60g) sprinkles

Instructions:

  1. Prepare the oven. Preheat your oven to 350°F (175°C). Grease your 9x13 inch pan with butter, then line the bottom with parchment paper for a clean release.
  2. Whisk dry ingredients. Combine the 280g flour, 300g sugar, 17g baking powder, and 5g salt in a large bowl. Mix until there are no clumps of baking powder.
  3. Incorporate butter. Add the 170g softened butter. Beat on low medium speed until the mixture looks like coarse sand. You shouldn't see any large chunks of butter remaining.
  4. Add wet ingredients. Slowly pour in the 240ml milk, 12ml vanilla, and 3 eggs. Mix on medium speed until the batter is smooth and pale. Don't overmix here or the cake will get tough.
  5. Bake the cake. Pour the batter into the pan and smooth the top with a spatula. Bake for 25 minutes until a toothpick inserted into the center comes out clean.
  6. Cool completely. Remove from the oven. Let it sit in the pan for 10 minutes, then move it to a wire rack. It must be cold before frosting, or the butter will melt.
  7. Cream the butter. Beat the 225g of frosting butter until it's light and fluffy.
  8. Add sugar. Gradually add the 500g sifted powdered sugar, one cup at a time. This prevents a sugar cloud in your kitchen.
  9. Whip the frosting. Stir in 30ml heavy cream and 5ml vanilla. Whip on high for 3 minutes until the frosting holds a stiff peak.
  10. Decorate. Spread a thick layer over the cake and top with 60g of sprinkles.