Preheat oven to 350 degrees.

In a bowl, cream shortening, butter, and sugar together. Then beat in the eggs until fluffy.

Mix in the flour, cream of tartar, baking soda, and salt until combined.

In another bowl, mix sugar and cinnamon together. Roll dough into walnut sized balls and roll in the cinnamon sugar.

Bake at 350 degrees for 8-10 minutes until lightly browned but still soft. Makes 3 dozen cookies.