Preheat your oven to 350°F (175°C). Line an 8x8 square baking pan with parchment paper, leaving a little overhang on the sides for easy removal.

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

Add the vanilla extract and eggs, one at a time, beating well after each addition.

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

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

Fold in the semi-sweet chocolate chips.

Spread the cookie dough evenly into the prepared baking pan, smoothing the top with a spatula.

Sprinkle the top with mini red, white, and blue M&Ms and festive sprinkles. Gently press them into the surface so they stick.

Bake for 25 minutes, or until the top is golden brown and a toothpick inserted into the center comes out clean or with a few moist crumbs.

Let the cookie bars cool completely in the pan. Once cool, lift them out using the parchment paper and cut into 16 squares.