Heat oven to 425 F. Mix the butter, sugar, egg, and vanilla. In a separate bowl stir the dry ingredients, then add to sugar mixture alternatively with sour cream.
Place dough batter balls on greased baking sheet. Bake 8 to 10 minutes or until lightly browned. Cool completely before frosting (or just eat them plain!).
Notes
The dough will be sticky so be sure to place it in the fridge for 30 minutes or so. If you want to make any cutouts you will want to roll it out on a floured surface and also put some flour on your hands.