INGREDIENTS
1
Egg, large
1 tsp
Baking powder
1/4 tsp
Baking soda
1 2/3 cups
Cake flour
1 1/2 cups
Confectioners' sugar
2/3 cup
Granulated sugar
1 tsp
Salt
1
Sanding sugar
2 tsp
Vanilla
1/2 cup
Butter, unsalted
11/16 cup
Sour cream
sprinkles (optional)