Sugar Cinnamon Mixture - Add the sugar mixture together, mix and set aside.
Preheat oven to 350 degrees.
Using mixer, in mixing bowl add the chopped cold butter, both sugars, and mix until light and fluffy. Add eggs and vanilla extract. Mix until fully combined.
With the mixer on low speed, add the dry ingredients (flour, cream of tartar, baking soda and salt) to the wet ingredients and mix together until dough comes together.
Roll approximately 2 tablespoons of dough into a ball (or use a medium ice cream scooper, I used 1.5 tablespoons and heaped them with dough) and then roll in the cinnamon-sugar mixture to coat the cookies.
Line two cookie sheets with parchment paper and then place cinnamon-sugared cookie balls on baking sheets. Cookies will spread some, so space cookies about 2 inches apart.
Bake for about 10-12 minutes. Cookies may appear undone but will continue to bake on the warm baking sheet. Leave cookies to cool on baking sheet for 10 minutes, then gently transfer to a wire rack to cool completely.
Store cookies at room temperature in an airtight container for up to 3 days. Cookies can also be frozen for up to 2 months.
