Mix:
  1/2 cup butter
  1/2 cup shortening
  1 and 1/2 cups sugar
  2 eggs
  2 and 1/2 cups flour

Add:
  2 tsp. cream of tartar
  1 tsp. baking soda
  1/4 tsp. salt

Separately mix 2 tbsp. cinnamon and 1/4 cup sugar.

Make balls of dough and roll in the cinnamon-sugar mixture.

Place on an ungreased cookie sheet at least 2 inches apart.

Bake for about 10 minutes at 400 degrees.