Preheat oven to 375°F (190°C) and line two baking sheets with parchment paper.

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

Add the egg, peppermint extract, and green food coloring; beat until well combined and the color is uniform.

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

Gradually incorporate the dry ingredients into the wet ingredients, mixing just until combined.

Fold in the semi-sweet chocolate chips by hand.

Drop rounded tablespoons of dough onto the prepared baking sheets, spaced approximately 2 inches apart.

Bake for 8 to 10 minutes until the edges are just set but the centers remain soft.

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