Colorful Sparkling Sugar Cookies

½ cup butter
½ cup shortening
½ cup sugar
½ cup sifted powdered sugar
½ tsp. Baking soda
½ tsp. Cream of tartar
1/8 tsp. Salt
1 egg
½ tsp. Vanilla
2 cups flour
sugar

In a large mixing bowl, beat the butter and the shortening with an electric mixer for 30 seconds. Add the ½ cup sugar, powdered sugar, baking soda, cream of tartar and the salt. Beat till combined.
Beat in egg and vanilla. Beat in as much flour as you can with the mixer. Stir in any remaining flour. Cover and chill dough in the refrigerator for about 3 hours or till it’s easy to handle.
Shape the dough into 1-inch balls. Roll balls in additional granulated sugar to coat. Place balls 3 inches apart on an ungreased cookie sheet. Flatten to 2 ½ inch rounds, using the bottom of a glass dipped in additional granulated sugar to prevent sticking, if you like.
Bake the cookies in a 350 degree oven for 7 to 9 minutes or till they’re lightly browned. Decorate as you like or leave plain. Makes about 40 cookies.