Go Back
+ servings
Rainbow Cupcakes
Print

Rainbow Cupcakes

You'll love these Rainbow Cupcakes. They are moist and fluffy, a vibrant celebration of joy, perfect for birthdays, parties, or any occasion.
Course Dessert
Cuisine American
Keyword cupcakes, rainbow
Prep Time 30 minutes
Cook Time 16 minutes
Decorate/Idle Time 1 hour
Total Time 1 hour 46 minutes
Servings 24 servings
Calories 305kcal

Equipment

  • cupcake pans
  • piping bags & tips

Ingredients

Cupcakes

  • 1 ⅔ cup granulated sugar
  • ½ cup unsalted butter softened
  • 6 egg whites
  • ¼ cup cooking oil - canola or vegetable
  • 1 tsp vanilla
  • 1 ¼ cup milk
  • 2 cup all-purpose flour
  • 2 ½ tsp baking powder
  • ½ tsp salt

Frosting

  • 1 cup butter unsalted, softened
  • 1 tsp vanilla
  • 1 tsp salt
  • 4 cup confectioner’s sugar
  • 3 tbsp milk

Food coloring - purple, blue, pink, orange, yellow, green

    Mini marshmallows - to decorate

      Instructions

      Cupcakes

      • Preheat the oven to 350 degrees.
      • Prep the muffin tins with liners and set aside.
      • In the bowl of a stand mixer, combine the sugar and softened butter. Beat until smooth.
      • Add in the egg whites, oil, and vanilla. Mix well.
      • Beat in the milk and mix to combine. The mixture may appear curdled - this is normal.
      • Add in the flour, baking powder, and salt and mix well. Stop the machine, scrape down the sides, and mix again.
      • Measure out the batter and fill each cavity until about ½ - ⅔ full.
      • Bake in the preheated oven for approximately 14 minutes or until the cupcakes are golden brown and the center is set.
      • Allow the cupcakes to cool completely before decorating.

      Frosting

      • In the bowl of a stand mixer, combine half of the confectioner’s sugar with the butter, vanilla, and salt.
      • Mix on low speed until combined.
      • Add in the remaining confectioner’s sugar and the milk.
      • Mix on low speed until combined.
      • Once combined, increase the speed to medium and beat for an additional minute until the frosting is fluffy and smooth.
      • Divide the frosting - measuring out a ½ cup for each of the colors. The remaining frosting will stay white and it can be transferred to a piping bag.
      • Tint each of the colors and transfer to individual piping bags.
      • Line out a strip of plastic wrap approximately 18-24 inches long.
      • Pipe each color of frosting onto the plastic wrap in rainbow order - purple, blue, green, yellow, orange, and then pink.
      • Roll the plastic wrap so that the colors overlap.
      • Place the log of frosting into a large piping bag fitted with a large star tip.

      Decorate

      • Once the cupcakes are cool, pipe a small mound of white frosting onto each cupcake.
      • Use a butter knife or offset spatula to spread and flatten the frosting to the edges.
      • Use the colored frosting bag to create an inverted “U” or horseshoe shape. Twist the piping bag mid-squeeze to show all the colors and add dimension.
      • Immediately place the mini marshmallow “clouds” before the frosting crusts over.

      Notes

      Storage: Cupcakes should be stored in an airtight container in the fridge for up to 3 days or frozen for 3 months.

      Nutrition

      Serving: 1serving | Calories: 305kcal | Carbohydrates: 43g | Protein: 2g | Fat: 14g | Saturated Fat: 3g | Cholesterol: 32mg | Sodium: 260mg | Potassium: 40mg | Fiber: 0.3g | Sugar: 34g | Calcium: 46mg | Iron: 1mg | Net Carbohydrates: 22g