Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

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

Beat in the eggs one at a time, mixing well after each addition, then add the vanilla extract.

In another bowl, whisk together the flour, baking powder, salt, and cinnamon.

Gradually add the dry mixture to the wet mixture, mixing until just combined.

Take tablespoon-sized amounts of dough and roll them into balls.

In a shallow bowl, mix the sugar with the remaining cinnamon, then roll each ball in this mixture until fully coated.

Place the coated dough balls on the prepared baking sheet, spacing them 2 inches apart.

Bake for 10-12 minutes, or until the edges are lightly golden.

Allow to cool slightly before transferring to a wire rack.