Grasshopper Dessert

1 cup chocolate wafer cookie crumbs
1/4 cup melted butter
1 jar (7 ounces) marshmallow creme
2 tablespoons creme de menthe
2 tablespoons creme de cacao
green food coloring
1 cup whipping cream

Reserve about 1 tablespoon of cookie crumbs for the topping; toss remaining crumbs with melted butter. Press crumbs in bottom of an 8-inch square baking pan. In a small bowl, combine marshmallow, liqueurs, and food coloring if using. Whip until light and fluffy. Whip the whipping cream in another bowl; fold into the marshmallow mixture. Spoon over cookie crumb crust; sprinkle reserved crumbs over the top. Freeze grasshopper dessert for about 8 hours or overnight. Cut grasshopper dessert in squares.