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

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

Beat in the egg and vanilla extract until well combined.

In a separate bowl, whisk together the flour, baking soda, salt, and ground cinnamon.

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

Roll the dough into 1-inch balls and place them 2 inches apart on the prepared baking sheets.

Flatten each cookie slightly with the palm of your hand or the bottom of a glass.

Bake for 10-12 minutes or until the edges are set and just beginning to brown.

Allow cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.