3 1/4 cups all-purpose flour, sift before measuring
1 tsp baking soda
1/2 tsp salt
1/2 cup butter, room teperature
1 cup granulated sugar
1 1/2 tsp vanilla
1/2 cup sour cream
Into a bowl, sift together the sifted flour, baking soda and salt. In a mixing bowl, cream butter, sugar, egg and vanilla with an electric mixer. Beat for 2 minutes. Add sour cream and half of the sifted dry ingredients; beat 1 minute.
Stir in remaining dry ingredietns with a wooden spoon. Divide dough in half and roll each portion out on a lightly flour surface to 1/4" thick. Cut with floured cookie cutter. Place cookies on greased cookie sheet.
Bake at 400 degrees for 8-10 minutes. Do not overbake or they will not be soft, which is the best part. Store soft sugar cookies in an airtight container.