Cream together the butter, 1 1/2 cups of sugar and eggs until smooth. In a separate bowl, use a whisk or fork to combine the flour, cream of tartar, baking soda, and salt. Add the dry mixture to the wet mixture and mix until well combined. Cover the dough and chill for at least 30 minutes but up to 24 hours before working with it.

Preheat oven to 400°F. Line cookie sheets with silpats or parchment paper.

Use a fork to combine the remaining 2 tablespoons of sugar with the 2 teaspoons of ground cinnamon.

Use a small disher (cookie scoop) or teaspoons to scoop about 2 teaspoons of cookie dough, roll it into a ball and then roll them in the cinnamon sugar to coat. Place the cookies 2-inches apart on the cookie sheets. Bake for 8-10 minutes, or until lightly browned but still soft. Let them rest on the cookie sheets for one minute before transferring to a cooling rack.

Store at room temperature in an airtight container.