In a large bowl, use a mixer to beat together the softened unsalted butter and packed light brown sugar until light and fluffy, about 3 minutes.

Incorporate the egg and vanilla extract, and beat until smooth and well combined.

In a separate bowl, whisk together all-purpose flour, baking soda, ground cinnamon, and salt until fully mixed.

Gradually add the dry ingredients to the wet mixture, mixing just until a dough forms.

In a shallow dish, combine granulated sugar and ground cinnamon for the topping.

Scoop out dough into 1.5-inch balls and roll them in the cinnamon sugar if desired.

For the best cookie texture, refrigerate the dough for at least 30 minutes.

Preheat your oven to 350°F (175°C).

Place the dough balls on a parchment-lined baking sheet, spacing them at least 2 inches apart.

Bake for 10-12 minutes or until the edges are golden brown while keeping the centers soft.

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