1 pkg. (15 oz.) Oreo cookies
1 stick butter, melted
2 pkgs. instant pistachio pudding
2 2/3 c. milk
1 carton (8 oz.) Cool Whip

Crush cookies. Add melted butter. Pat 2/3 mixture into 9 x 13 inch pan. Mix pudding with milk, when thick, fold in Cool Whip. Spread over crust. Sprinkle remaining cookies over top. Refrigerate and serve.