1/2 cup (115g) unsalted butter, softened to room temperature
3/4 cup (150g) granulated sugar
1 large egg + 1 egg yolk*
2 teaspoons vanilla extract
1 and 1/2 cups (190g) spoon & leveled Gold Medal all-purpose flour
1/4 teaspoon salt
1 teaspoon baking powder
1/2 teaspoon baking soda
1 and 1/2 teaspoons cornstarch
2/3 cup (120g) white chocolate chips
1/2 cup (80g) rainbow sprinkles (not nonpareils)*

Vanilla Almond Frosting

1/2 cup (115g) unsalted butter, softened to room temperature
1 and 3/4 cups (150g) confectioners' sugar
2 Tablespoons (30ml) heavy cream or half-and-half*
1 teaspoon vanilla extract
1/4 teaspoon almond extract*
salt, to taste
extra sprinkles for decorating on top