Preheat oven to 375 degrees F.
In a small shallow bowl, blend 2 t. of cinnamon & 3 Tbsp sugar together and set aside.
In a medium bowl, sift flour, baking soda, cream of tartar & salt together. Using an electric mixer, blend butter, sugar, eggs, and vanilla together. Mix until smooth.
Add flour mixture to butter mixture gradually, mixing well to form cookie dough.
Using a tablespoon, scoop out dough and roll into a ball, roll in the cinnamon-sugar mixture then place on a cookie sheet. Continue with remainder of dough, placing cookies 1 inch apart on the cookie sheet. These cookies will spread.
Bake at 375 for 10-12 minutes or until golden brown.
Remove from oven and cool on rack before serving.
These light, buttery cookies are the perfect sweet treat. Make a double batch to share with friends.