For the cupcakes:
- 1/2 cup (1 stick) unsalted butter
- 3/4 cup plus 2 tablespoons cake flour
- 1/2 cup plus 2 tablespoons all-purpose flour
- 3/4 cup plus 2 tablespoons granulated sugar
- 1 1/4 teaspoons baking powder
- 1/2 teaspoon salt
- 2 eggs
- 1/2 cup milk
- 1 teaspoon vanilla
- 1/4 cup rainbow-colored sprinkles, plus more for topping
For the buttercream frosting:
- 1 cup (2 sticks) unsalted butter, softened
- 1/3 cup packed light brown sugar
- 1 teaspoon vanilla
- 2 1/2 to 3 cups powdered sugar
- In a small saucepan over medium heat, melt butter. Continue to cook butter, stirring constantly, until brown bits form and butter turns a golden, caramel color. Remove from heat. Pour butter into a small bowl or cup. Cover and chill in fridge at least 4 hours until hardened again. When ready to make cupcakes, remove butter from fridge and bring to room temperature. Cut into small cubes.
- Heat oven to 350 degrees F. Lightly grease two 24-cup mini muffin tins with baking spray.
- In a large bowl or bowl of a stand mixer, whisk flours, sugar, baking powder and salt (with paddle attachment, if using a stand mixer) until well combined. Gradually add the cubed butter and stir 1 to 2 minutes until mixture resembles coarse crumbs.
- Add eggs, milk and vanilla; stir until just combined. Increase speed to medium and beat 2 minutes, scraping sides of bowl occasionally, until mixture is light and smooth. Fold in sprinkles.
- Fill prepared muffin tin cups 2/3 full with batter. Bake 15 minutes until a toothpick inserted in the center comes out clean. Cool cupcakes 10 minutes in pan, then transfer to a cooling rack to cool completely.
- To make the buttercream: Cream butter and brown sugar in a stand mixer (or in a large bowl using an electric hand mixer). Add vanilla; stir to combine. Gradually add enough powdered sugar until a stiff but smooth frosting forms. Transfer frosting to a piping bag.
- Pipe frosting on top of fully cooled cupcakes. Sprinkle tops with extra sprinkles. If using push pops, stack two mini cupcakes on top of each other and carefully place inside a push pop. Repeat with remaining cupcakes/push pops.