- 3/4 cup unsalted butter,softened
- 2/3 cup plus 1/2 cup sugar, divided
- 2 eggs
- 1 tsp vanilla extract
- 2 3/4 cups flour
- 1 tsp baking soda
- 1 tsp cream of tartar
- 1/2 tsp salt
- 2 tsp cinnamon
in a lg bowl, using an electric mixer on high, beat butter and 2/3 cup sugar until light and fluffy, about 3 min. beat in eggs, one at a time, incorporating completely after each addition. beat in vanilla. reduce speed to low; add flour, baking soda, cream of tartar, and salt and mix on low until a stiff dough forms. cover and refrigerate at least 2 hours or up to 1 day.
preheat oven to 350 and line 2 baking sheets with parchment paper.
combine 1/2 cup sugar and the cinnamon in a med bowl. shape dough into 1 1/2 inch balls and place on prepared pans. refrigerate 10 min, then roll in sugar mixture and arrange about 2 inches apart on pans. using the bottom of a glass dipped in flour, slightly flatten each ball. bake 10-12 min, until set around the edges and slightly soft in the center. let cool on wire racks.