Preheat oven to 400˚F. Line 2 or 3 baking sheet with parchment and set aside.
In a large bowl combine flour, cream of tartar, baking soda, and salt. Whisk together and set aside.
In the bowl of a stand mixer (or using an electric mixer), cream together butter and sugar with a paddle attachment for 2 to 3 minutes, until mixture is fluffy.
Add eggs and vanilla to butter mixture and continue to beat together.
Add dry mixture to wet mixture and mixture together until a dough forms. Don't over-mix the dough.
In a small bowl combine sugar and cinnamon and whisk together.
Scoop 1 tablespoon sized balls of dough and roll into balls.
Roll each ball of dough into the cinnamon-sugar mixture until each ball is fully covered.
Place cookies onto the prepared baking sheet about 1 ½ inches apart.
Bake the cookies for about 9 minutes or until cookies have puffed up, the cinnamon-sugar coating has darkened and the cookies have a slight crack on top.
Remove cookies from the oven and cool for a few minutes before transferring to a cooling rack or serving.
