Ingredients:

  • 1.5 cups (190g) all-purpose flour
  • 1 cup (200g) granulated sugar
  • 1.5 tsp (7g) baking powder
  • 0.5 tsp (3g) salt
  • 0.5 cup (113g) unsalted butter, softened
  • 1 large egg (50g)
  • 0.5 cup (120ml) whole milk
  • 1 tsp (5ml) vanilla extract
  • 0.25 cup (30g) rainbow sprinkles (jimmies)
  • 1 cup (225g) unsalted butter, softened
  • 3 cups (360g) powdered sugar
  • 2 tbsp (30ml) heavy cream
  • 1 tsp (5ml) vanilla bean paste
  • 0.5 cup (60g) rainbow nonpareil sprinkles

Instructions:

  1. Cream the softened butter and sugar together on medium-high speed until the mixture looks pale and fluffy.
  2. Beat in the egg and vanilla extract until fully incorporated.
  3. Gradually add the flour, baking powder, and salt, alternating with the whole milk, mixing only until the streaks of flour disappear.
  4. Gently fold in the rainbow jimmies using a rubber spatula to avoid over-mixing.
  5. Grease the ramekins thoroughly and divide the batter equally between them.
  6. Bake at 350°F (175°C) for 28–33 minutes, or until a toothpick inserted in the center comes out clean and the edges begin to pull away from the sides.
  7. Cool the cakes in the pans for 10 minutes before transferring to a wire rack to cool completely.
  8. Whip the butter, powdered sugar, heavy cream, and vanilla bean paste until the frosting is stiff but spreadable.
  9. Apply a generous layer of frosting to the top of each cooled cake, smoothing it into a flat disc.
  10. Immediately pour a heap of nonpareils over the center and press them gently into the frosting using the palm of your hand or a flat spatula.