Preheat your oven to 375°F and line your baking sheets with parchment paper.
Cream together the butter and sugar, then add in the eggs one at a time, incorporating each one thoroughly. When done, add the vanilla.
Whisk together your dry ingredients, then add it to the butter mixture, mixing until the dough is smooth.
Combine the white sugar and cinnamon in a bowl.
Roll a tablespoon sized amount of cookie dough into a ball, then roll in the cinnamon mixture, covering completely.
Place on the baking sheets and bake for 8-10 minutes, until the bottoms of the cookies are browned and the edges of the cookies are set. Do not overbake.
Remove from the oven and let cool for 2-3 minutes. Remove from the baking sheets onto a cookie rack and cool completely.
Notes
You can try all shortening for the REAL old fashioned Snickerdoodle cookie recipe, or half butter and half shortening. It really is up to your personal likes!