Combine wet ingredients. In a large mixing bowl with an electric mixer, cream together butter, sugar, eggs and vanilla on medium-high speed until light and fluffy, about 2 minutes. You can use a hand mixer, or a stand mixer with a paddle attachment. 1 cup (2 sticks, 226 g) unsalted butter, softened 1 ½ cups (300 g) granulated white sugar 2 large eggs 2 teaspoons vanilla extract
Add dry ingredients. With mixer on low, blend in the flour, cream of tartar, soda and salt until evenly combined. 2 3/4 cups (330 g) all-purpose flour 2 teaspoons cream of tartar 1 teaspoons baking soda ¼ teaspoon table salt
Chill the cookie dough. Cover the bowl with plastic wrap and refrigerate for 1 hour. This dough is sticky so it’s best to chill the dough for at least 1 hour or you can leave to refrigerate up to overnight.
Preheat and prepare cookie sheets. Near the end of the chilling time, position a rack in the center of the oven and preheat oven to 400oF (205°C). Line two cookie sheets with parchment paper or silicone baking mat.
Make cinnamon sugar topping. Mix together the sugar and cinnamon in a small bowl. 4 tablespoons granulated white sugar 4 teaspoons ground cinnamon
Shape and roll cookies. Using a 1-inch cookie scoop or a tablespoon scoop the cookies into 1 ½ inch balls and immediately drop the cookie balls into the cinnamon sugar mixture to coat. Place 2 inches apart on prepared baking sheets.
Bake and cool cookies. Bake in the preheated 400°F (205°C) oven 8-10 minutes, or until edges are browned, and tops are slightly puffy and set but not too hard. Remove from the oven and let cool on the baking sheet for 5 minutes. Transfer to a wire cooling rack to cool completely.