Servings: 30 cookies Prep Time: 15 minutes Cooking Time: 15 minutes + 15 minutes for cooling Ingredients: 2 1/4 cups all-purpose flour 2 tsp. cream of tartar 1 tsp. baking soda 1/2 tsp. salt 12 tbsp. unsalted butter, softened 1/4 cup vegetable shortening 1 1/2 cups sugar, plus 3 tbsp. for rolling dough 2 large