Preheat oven to 350°F (175°C). Line baking sheets with parchment.
In a large bowl, beat butter and sugar until light and fluffy (about 2 minutes).
Add egg and peppermint extract; beat until combined.
Whisk flour, baking soda, baking powder, and salt in a separate bowl.
Add green food coloring (optional) and mix just until color is even.
Fold in chopped Andes Mints and chocolate chips.
Scoop 1.5-tablespoon dough balls onto baking sheets, spacing 2 inches apart.
Bake 10–12 minutes, rotating pans halfway through.
Let cool on baking sheet for 10 minutes, then transfer to a wire rack.