Ingredients:

  • 3 cups (375g) all-purpose flour
  • 2 cups (400g) granulated sugar
  • 1 tbsp (12g) baking powder
  • ½ tsp (3g) salt
  • 1 cup (225g) unsalted butter, softened
  • 4 large eggs (approx. 200g)
  • 1 cup (240ml) whole milk, room temperature
  • 2 tsp (10ml) pure vanilla extract
  • 1 tsp (5ml) red gel food coloring
  • 1 tsp (5ml) blue gel food coloring
  • 1 ½ cups (340g) unsalted butter, softened
  • 5 cups (600g) powdered sugar, sifted
  • 3 tbsp (45ml) heavy cream
  • 1 tsp (5ml) vanilla extract
  • ¼ tsp (1.5g) fine sea salt

Instructions:

  1. Cream the softened butter and sugar until the mixture looks pale and fluffy.
  2. Beat in the eggs one at a time, followed by the vanilla extract.
  3. Sift together the flour, baking powder, and salt; gradually add the dry ingredients to the butter mixture, alternating with the milk, until the batter is smooth.
  4. Split the batter evenly between three medium bowls. Leave the first bowl white, stir red gel into the second bowl, and blue gel into the third.
  5. Pour each colored batter into parchment-lined 8-inch round cake pans.
  6. Bake at 350°F (175°C) for 25-30 minutes or until a toothpick inserted in the center comes out clean.
  7. Allow cakes to cool completely on a wire rack for 2 hours.
  8. Level the tops of the cooled cakes using a serrated knife.
  9. Prepare buttercream by beating together softened butter, powdered sugar, heavy cream, vanilla extract, and salt.
  10. Assemble the cake by placing the blue layer at the bottom, spreading a layer of buttercream, followed by the white layer, another layer of buttercream, and finally the red layer on top.