Preheat the oven to 400 degrees and line baking sheets with parchment paper or grease the cookie sheet. Mix 2 teaspoons cinnamon and 1/4 cup sugar in a small bowl. Set aside. Beat butter and sugar together. Beat in eggs and vanilla. Mix in cream of tartar, salt, baking soda and flour. Scoop cookie dough using a 3 Tbsp. scoop (large cookies) or 2 Tbsp. scoop (regular cookies). Roll cookie dough balls in cinnamon and sugar mixture then place onto baking sheets. Bake cookies 10-11 minutes for large cookies or 8-9 minutes for regular cookies. Immediately remove cookies from baking sheet and transfer to a wire cooling rack. Notes This recipe makes 18 large cookies or 27 regular cookies.