Ingredients:

  • 1 ½ cups (190g) all-purpose flour
  • 1 cup (200g) granulated sugar
  • 1 ½ tsp (7g) baking powder
  • ½ tsp (3g) salt
  • ½ cup (115g) unsalted butter, softened
  • 1 large egg (50g)
  • ¾ cup (180ml) whole milk
  • 2 tsp (10ml) pure vanilla extract
  • 1 cup (225g) unsalted butter, softened
  • 4 cups (480g) powdered sugar, sifted
  • 2 tbsp (30ml) heavy cream
  • 1 tsp (5ml) pure vanilla extract
  • 1 pinch (1g) salt
  • ½ cup (60g) rainbow nonpareils

Instructions:

  1. Preheat your oven to 350°F (175°C). In a large bowl, cream together the softened butter and sugar until the mixture looks pale and fluffy. Beat in the egg and vanilla extract until fully incorporated. Slowly stir in the flour, baking powder, and salt, alternating with the milk, until the batter is smooth.
  2. Divide the batter evenly among 8 ramekins. Bake for 25-30 minutes until the edges pull slightly away from the sides and a toothpick inserted into the center comes out clean. Let the cakes cool completely in the containers before frosting.
  3. Beat the softened butter on medium-high speed until creamy. Gradually add the powdered sugar one cup at a time, ensuring each addition is fully integrated. Stir in the heavy cream, vanilla, and salt. Whip on high for 2 minutes until the texture is velvety and holds a stiff peak.
  4. Transfer the buttercream into a piping bag. Pipe a high buttercream swirl onto each cooled cake and immediately top with rainbow nonpareils to ensure adhesion.