Step 1

First, preheat the oven to Spray a mini 6" cake pan that has 2" high sides with cooking spray. Line the bottom of the pan with parchment paper (trace it on a piece of parchment paper, cut it out, and fit it in).

Step 2

Next, beat together the butter and sugar with an electric mixer until light and fluffy, about 1-2 minutes.

Step 3

Add the vanilla and egg white and beat until well-mixed.

Step 4

Add the flour, baking powder, and salt and beat for just a few seconds to combine it, and then add all of the milk. Beat until smooth, but do not over mix.

Step 5

Stir in the sprinkles.

Step 6

Pour the cake batter into the prepared pan, and place it on a baking sheet. Bake for 30 minutes, or until a toothpick inserted comes out with only moist crumbs clinging to it.

Step 7

Let the cake cool slightly before gently tipping it onto a plate--it should come out easily. Peel the parchment paper off the top of the cake.

Step 8

Meanwhile, beat together all of the frosting ingredients, except the sprinkles. Stir in the sprinkles last.

Step 9

Frost the cake, slice and serve.