Preheat oven at 350 degrees. Grease or paper-line a muffin pan. Sift together flour, baking soda, and baking powder. Set aside. In a mixing bowl, beat together butter and sugar. Beat in eggs one at a time, making sure each is beaten thoroughly. Add the lemon peel and the vanilla. Add in dry ingredients, alternating with the sour cream. Batter will be thick. Fill the muffin pans so that they are about 1/4 cup full. Bake for about 25-30 minutes or until golden brown. Let cool for about 10 minutes.