Line the bottom and sides of a 11 x 7 inch baking dish with aluminum foil, leaving a slight overhang.

Coat the aluminum foil with a non-stick cooking spray.

Preheat oven to 350 degrees Fahrenheit.

Combine butter, sugars, and cocoa in a large mixing bowl until well blended.

Add eggs one at a time, and beat well after each addition.

Combine flour and baking powder; Add to cocoa mixture.

Stir in vanilla and crushed cookies.

Pour mixture into baking dish.

Bake for 25 to 30 minutes or until toothpick inserted near center comes out with moist crumbs. Do not over bake.

Immediately pour baking chips evenly over top of brownies.

Drag a toothpick in parallel lines over the mint frosting, to create a swirl pattern.