Scintillating cinnamon

These snickerdoodles are so yummy. I could/would/did eat a whole plate's worth in one sitting. They are simple and economical as far as cookies go. Thanks to good old Betty Crocker for this one.

THE RECIPE:

1 1/2 c. sugar
1/2 c. butter, slightly softened
1/2 c. shortening
2 eggs
2 3/4 c. flour
2 tsp. cream of tartar
1 tsp. baking soda
1/4 tsp. salt
1/4 c. sugar
2 tsp. ground cinnamon

Heat oven to 400 degrees. Mix 1 1/2 cups sugar, butter, shortening and eggs. Stir in flour, cream of tartar, baking soda and salt. In separate, small bowl, mix 1/4 cup sugar and cinnamon. Shape dough into 1 1/4-inch balls, then roll in cinnamon mixture. Place 2 inches apart on ungreased cookie sheet. Bake 8 to 10 minutes. Even when they are done, they will still seem a little doughy between the cracks on top. Don't overbake, or cookies will be crunchy when cooled. Cool on wire rack.