Preheat oven to 350 or what your box mix suggests. Spray at 9 X 13 pan with cooking spray
Line Cake Pan with Oreo Cookies for Crust.
Mix cake as directed on box.
Pour over cookies. Bake as directed.
Just before cake comes out Make pudding in large bowl.
I like to check my cake about 5 minutes before timer goes off to check doneness.
Using the end of wooden spoon make about 40 to 50 holes on top of cake. Pour pudding into holes. Make sure you do this right away or pudding will be too thick.
Leave on counter until cake cools.This way the pudding can saturate the holes.
Refrigerate about 1 hour. Top cake with cool whip and take 5 - 6 cookies and crumble and pour on top.