Preheat your oven to 350°F.
Mix together the dry ingredients: flour, baking soda, salt, and cinnamon in a medium bowl.
Cream the butter, brown sugar, and granulated sugar together until light and fluffy, about 2-3 minutes.
Beat in the egg and vanilla extract, then gradually add the dry ingredients until just combined.
Drop rounded balls of dough onto prepared baking sheets, spaced 2 inches apart.
Bake for 10-12 minutes until edges are lightly golden. Let cool on baking sheets for 5 minutes before transferring to a wire rack.