Preheat & Prepare – Heat the oven to 350°F and line a baking sheet with parchment paper.
Creamy Base – In a bowl, beat butter and sugar until light and fluffy.
Color & Flavor Infusion – Mix in the egg, mint extract, and green food coloring until well combined.
Dry Ingredients Magic – Gradually add flour, baking soda, baking powder, cream of tartar, and salt, mixing until fully incorporated.
Fold in the Fun – Gently stir in mint chocolate chips and Lucky Charms marshmallows.
Shape & Bake – Roll the dough into small balls, place on a baking sheet, and bake for 10 minutes until lightly golden.
Cool & Enjoy – Let cookies cool for 2 minutes before transferring to a wire rack.