In a stand mixer, combine cake mix, cool whip, egg & mint extract. Scrape bowl & re-mix until no cool whip streaks appear. (Do NOT use a hand mixer, the dough is thick.)
Scoop balls of cookie dough & dredge (coat) the outside of the cookie dough in a bowl filled with the green sugar crystals. Flatten cookie dough until about ¾″ thick on a parchment lined baking sheet. Place an unwrapped mint truffle kiss in the center. Repeat with each cookie.
Bake at 350˚F for 10-12 minutes or until the cookies have spread, cracked & look done.
Smooth the tip of the melted kiss with the back of a spoon. Heat the chocolate chips in a bowl in the microwave 30 seconds at a time until melted. Place in a plastic bag with the corner cut off. Zig-zag the tops of the cookies. Allow to cool completely before removing from pan & packaging for friends/neighbors. You can place cookies in the fridge to speed the process along. Enjoy!