Preheat your oven to 350°F (175°C).
In a bowl, whisk together flour, baking soda, and cream of tartar.
In a separate bowl, cream together the softened butter and sugar until light and fluffy.
Add eggs one at a time, mixing well after each addition.
Stir in the vanilla extract.
Gradually add the dry ingredients to the wet mixture, mixing until just combined.
In a small bowl, combine the sugar and cinnamon for rolling.
Shape the dough into balls and roll them in the cinnamon-sugar mixture.
Place the dough balls on a baking sheet, spaced about 2 inches apart.
Bake for 10-12 minutes, or until the edges are golden brown.
Allow cookies to cool on the baking sheet for a few minutes before transferring them to a wire rack.