In the bowl of your stand mixer combine the butter and sugars. Beat well until light and fluffy, approximately 5 minutes.
1 cup unsalted butter, softened, 1 cup white granulated sugar, ½ cup light brown sugar, packed
Add the eggs and the vanilla extract. Beat again for 3 - 5 minutes, scraping down the sides occasionally using a rubber spatula.
2 eggs, 2 tsp vanilla extract
Meanwhile, in a medium size bowl whisk together the dry ingredients.
2½ cups all-purpose flour, 1½ tsp cream of tartar, 1 tsp baking soda, ½ tsp cinnamon, ¼ tsp salt
Add the dry ingredients to the wet ingredients and with the mixer speed set to medium, mix until just combined.
In a small bowl combined the ingredients for the topping.
⅓ cup white granulated sugar, 2½ tsp cinnamon
Using a mini ice cream scooper, or a tablespoon form balls with the dough; you should make approximately 40 balls of cookie dough. Roll them into the cinnamon sugar mixture.
Place balls on a parchment lined cookie sheet. Bake in middle of the oven for 10 - 13 minutes, or until the bottoms are lightly browned.
Allow to cool on baking tray for a few minutes before transferring to a cooling rack. Enjoy!
Notes
Snickerdoodles keep in a well sealed container at room temperature for a week. Keep cookies in the refrigerator for longer storage. Cookies, and unbaked cookie dough, can also be frozen.