2 c. flour
3/4 tsp. baking soda
1 tsp. cream of tartar
1/4 tsp. salt
1 c. powdered sugar
1/2 c. firm butter
1/2 c. shortening
1 egg
1 tsp. vanilla
Granulated sugar for rolling

Sift dry ingredients into bowl. Cut in butter and shortening until mix resembles coarse crumbs. Blend together egg and vanilla. Add to dry ingredients; mix only until blended. Dough will be fairly soft. Shape into 1 inch balls. Roll in granulated sugar. Place 2 inches apart on ungreased cookie sheet. Flatten to 1/4 inch thickness with bottom of glass dipped in sugar. Bake at 350 degrees for about 12 minutes or until delicately browned. At Christmas time can be rolled in colored sugar.