Place Oreos into a food processor and crush until fine crumbs. Place in a medium bowl and stir in melted butter. Press crumbs into a buttered 9-inch pie plate.
Place in freezer while you make the pie filling.
You can make this in a 9 or 10-inch pie plate. If you make it in a 10-inch it will not be quite at thick/tall as what you see in the pictures. Either size works great though.