Preheat oven to 350F. Line 3 cookie sheets with parchment paper or silicone baking mats.
In a medium bowl, toss together the flour, cream of tarter, baking soda, and salt. In a small bowl, toss together the 1/4 cup sugar and 1 tbsp of cinnamon. Set both aside.
2 & 3/4 cups (345g) all-purpose flour, 2 tsp cream of tartar, 1 tsp baking soda*, 1/2 tsp salt
In a large bowl, cream together the butter, granulated sugar and brown sugar. Mix in the eggs and vanilla until blended.
1 cup (227g) unsalted butter, 1 cup (200g) granulated sugar, 1/4 cup (50g) brown sugar, 2 large eggs, 1 tsp vanilla
Add the dry ingredients to the wet ingredients and stir until combined.
Using a medium cookie scoop or tablespoon, roll out twelve 1.5" balls. Then roll them in the cinnamon-sugar mixture. Place them 2" apart on lined baking sheet. Repeat with rest of batter.
1/4 cup (50g) granulated sugar, 1 Tbsp ground cinnamon
Bake for 8-10 minutes or until the edges are lightly browned. Cool for 5 minutes and transfer to wire rack.
Notes
Leftovers can be stored at room temperature in an airtight container for up to 5 days.*You can replace both the cream of tarter and the baking soda for 4 tsp of baking powder for similar results.