1 pkg. Oreo cookies
1 lg. or 2 sm. boxes pistachio instant pudding
1 (12 oz.) container Cool Whip
1/2 gallon vanilla ice cream

First set out the ice cream and the Cool Whip so that they can soften. Next, in a 9 x 13 pan, crush 3/4 package of Oreos to make cookie crust. Set aside. In a large bowl, mix together ice cream, Cool Whip and dry pudding mix. Stir until combined. It should be hard to stir. Spread mixture over top of the crust. Top with remainder of Oreo cookie crumbs and chill for 8 hours.