Preheat the oven to 350°F (175°C).

Line a baking sheet with parchment paper.

In a mixing bowl, cream together the softened butter and granulated sugar until light and fluffy.

Add the eggs one at a time, mixing well after each addition.

In a separate bowl, whisk together the flour, cream of tartar, baking soda, and salt.

Gradually add the dry ingredients into the butter mixture and mix until just combined.

In a small bowl, combine 3 tablespoons granulated sugar and 2 teaspoons ground cinnamon.

Roll the dough into 1-inch balls and coat each in the cinnamon sugar mixture.

Place the dough balls 2 inches apart on the prepared baking sheet.

Bake for 10 to 12 minutes or until edges are lightly golden.

Cool the cookies on the baking sheet for 5 minutes, then transfer to a cooling rack to cool completely.