Preheat your oven to 375°F (190°C). Line two baking sheets with parchment paper or silicone baking mats.
In a medium bowl, whisk together the all-purpose flour, baking soda, cream of tartar, and salt. Set aside.
In a large bowl, use an electric mixer to cream the softened butter, granulated sugar, and brown sugar together until light and fluffy, about 3 to 4 minutes.
Beat in the eggs, one at a time, ensuring each is fully incorporated before adding the next. Stir in the vanilla extract.
Gradually add the dry ingredients to the wet ingredients, mixing just until combined. Avoid overmixing.
In a small bowl, mix together 1/4 cup granulated sugar and 2 teaspoons ground cinnamon.
Scoop out generous tablespoon-sized portions of dough and roll each into a ball. Roll the dough balls in the cinnamon sugar mixture until fully coated.
Place the coated dough balls on the prepared baking sheets, spacing them about 2 inches apart. Bake for 9–11 minutes, or until edges are set and tops have a crackled appearance but are still soft to the touch.
Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.