In a medium sized bowl whisk the flour, cream of tartar, baking soda, and salt. Set aside.
In the bowl of a stand mixer fitted with a paddle attachment, cream the butter and sugar on medium high speed for 3 minutes. The mixture should be light and fluffy. Scrape down the sides of the bowl. Add the eggs and vanilla and beat for 1 more minute on medium speed.
Mix in the dry ingredients until just combined.
Cover the bowl with plastic wrap and refrigerate for 30 minutes.
Meanwhile, in a small bowl mix the sugar and cinnamon.
Preheat oven to 350°F. Line a baking sheet with parchment paper and set aside.
Remove the cookie dough from the fridge and portion into 1 ½ “ inch sized balls. (I used a 1 ½ T sized scoop to help portion out the dough). Roll each dough ball in the cinnamon sugar mixture 2 times. You want the cookies heavily coated.
Place the balls on the cookie sheet leaving 2 inches between each cookie. Bake for 9-11 minutes. The edges will turn a light golden color (you don’t want to overbake).
Remove from the oven and let cool on the baking sheet for several minutes, then transfer to a wire rack to cool completely.
Store in an airtight container for 5 days.