Rootbeer Rollout Cookies

1 cup margarine
1 1/2 cups powdered sugar
1 egg
1 teaspoon vanilla
1/4 teaspoon rootbeer flavored oil
2 1/2 cups flour
1/2 teaspoon baking soda
1/4 teaspoon cream of tartar

ICING:
1 1/2 cups powdered sugar
3 tablespoons butter
1/4 teaspoon rootbeer oil
1 1/2 tablespoons milk

Cream margarine and confectioners' sugar, beat in egg, add vanilla and rootbeer oil.

Add dry ingredients which have been sifted together. Wrap in plastic wrap and chill dough - 3 hours.

Roll out 1/8" thick  and cut into desired shapes.

Bake at 375ºF 5-7 minutes.