Preheat oven to 375 degrees F. Line a baking sheet with parchment paper.
Cream together shortening, sugar, eggs and vanilla. Mix for 2-3 minutes or until fully combined. Mix in cream of tartar, baking soda, salt, and flour. Continue to mix until dough forms. Meanwhile, combine sugar and cinnamon in a bowl.
Roll dough into balls (about 1 1/2 tablespoon per ball) and roll in cinnamon sugar. Place on cookie sheet and bake for 14 minutes.
Notes
Cookies will keep up to 1 week in an airtight container or up to 4 weeks in the freezer.
For chewier cookies, reduce baking time to 10 or 11 minutes.