Heat oven to 325°F. Line baking pans with parchment paper.
In a large bowl, sift flour, baking soda, cream of tartar, salt and cinnamon. Set aside.
In the bowl of an electric mixer, cream butter and sugars until fluffy. Slowly add egg, egg yolk, and vanilla; mix to incorporate and scrape down. Add flour mixture and mix until just fully incorporated. Refrigerate dough.
Scoop out dough and shape into balls with your hands. Roll balls into spiced sugar.
Arrange on baking pans; bake for 10-12 minutes. Makes 40 cookies.
Approximate Nutrient Analysis per serving per cookie:
120 calories, 5 g fat, 3 g saturated fat, 20 mg cholesterol, 100 mg sodium, 18 g carbohydrate, 0 g fiber, 12 g sugar, 1 g protein