Preheat your oven to 375°F (190°C). Line two baking sheets with parchment paper. Set aside.
Make the cookies: In a bowl, combine flour, baking soda, cream of tartar, cinnamon and salt. Mix well and set aside.
In a separate large bowl, cream butter and sugar for 4-5 minutes until light and fluffy. Scrape the sides of the bowl and add the eggs and vanilla. Cream for 1-2 minutes longer.
Gradually add flour mixture and mix until combined. Do it in two or three parts.
Make the topping: in a small bowl mix sugar and cinnamon.
Use a small cookie scoop to scoop out the dough and roll it into a ball. Roll each ball in the cinnamon-sugar mixture. Sprinkle extra cinnamon sugar on top if desired.
Arrange the cookies 2 inches apart on the prepared baking tray. Bake for 8-10 minutes.
Allow to cool for at least 10 minutes before removing the cookies from the pan.
