Ingredients:

  • 1 ½ cups (192g) all-purpose flour
  • 1 ½ teaspoons baking powder
  • ¼ teaspoon salt
  • ½ cup (1 stick or 113g) unsalted butter, softened
  • ¾ cup (150g) granulated sugar
  • 2 large eggs
  • 1 teaspoon vanilla extract
  • ½ cup (120ml) milk
  • 1 cup (2 sticks or 226g) unsalted butter, softened
  • 3 cups (360g) powdered sugar
  • ¼ cup (60ml) heavy cream
  • 1 teaspoon vanilla extract
  • ¼ cup (60ml) quinine water, (tonic water that contains quinine)
  • Optional: Blue food coloring (gel is preferred)

Instructions:

  1. Preheat oven to 350°F (175°C). Line muffin tin with paper liners.
  2. Whisk together flour, baking powder, and salt in a bowl.
  3. In a separate bowl, cream together butter and sugar until light and fluffy.
  4. Beat in eggs one at a time, then stir in vanilla extract.
  5. Gradually add the dry ingredients to the wet ingredients, alternating with the milk, beginning and ending with the dry ingredients. Mix until just combined.
  6. Fill cupcake liners about 2/3 full.
  7. Bake for 18-22 minutes, or until a toothpick inserted into the center comes out clean.
  8. Let cupcakes cool in the muffin tin for a few minutes, then transfer to a wire rack to cool completely.
  9. In a large bowl, beat the butter until light and fluffy.
  10. Gradually add the powdered sugar, beating on low speed until combined.
  11. Beat in the heavy cream and vanilla extract until smooth and creamy.
  12. Stir in the quinine water. If desired, add a few drops of blue food coloring until you reach your desired shade of moonlit blue.
  13. Once the cupcakes are completely cool, frost with the moonlit glow frosting.
  14. To see the full glow effect, check your cupcakes under UV light in a dark room.