Preheat oven to 400°F and line two baking sheets with parchment paper or silpat.
In a large bowl, whisk together the flour, cream of tartar, baking soda and salt. Set aside.
In the bowl of a stand mixer fitted with the paddle attachment, cream together the butter and 1 1/2 cups of sugar on medium speed until creamy.
Scrape down the sides of the bowl and while on low speed, add the eggs, one at a time. Scrape down the sides of the bowl and add the vanilla.
Slowly add in the flour mixture until just a few flour streaks remain. Turn off the mixer and give the dough a final stir by hand to mix in the remaining flour streaks.
In a small shallow bowl, mix together the remaining 1/4 cup of sugar and cinnamon until thoroughly blended.
Working with 2 tablespoons of dough at a time, roll the dough into a ball and coat in the cinnamon sugar mixture. Toss the coated ball in between cupped hands and give it a second coat in the cinnamon sugar mixture. Place the dough on the prepared baking sheet. Repeat with the remaining dough, spacing about 2 inches apart on the baking sheet.
Bake for 10 to 11 minutes, until the edges are just set and the centers are puffy. Allow to cool on the pan for 5 minutes before transferring to a cooling rack to cool completely.