Use 36 Oreo cookies

Crush 18 Oreo's and put in bottom of greased 9x13 pan. Melt 40 large marshmallows (or 5 cups miniature) in 1 cup milk. Add 6 tbsp. creme de menthe and cool. Blend in 12 oz. Cool Whip. Crush other 18 Oreo's and put crumbs on top. Freeze until stiff and then refrigerate.