Pour warmed fudge topping into medium bowl. Whisk in 1-1/2 cup of thawed Cool Whip. Add dry pudding mix; stir 2 minutes. Stir in chopped cookies.
Arrange 4 ice cream sandwiches, side-by-side, on a 24" long sheet of foil on top of whatever pan or sheet you plan to freeze it on. Top with half the Cool Whip mixture. Repeat layer of sandwiches. Repeat layer of Cool Whip mixture. Top with final sandwiches. Frost the top and sides with remaining Cool Whip. I actually used quite a bit more of Cool Whip to make sure of the coverage.
This part is the sticky and messy part. Bring up the sides of foil and top. This will help hold it's shape when freezing. Freeze at least four hours. I froze mine overnight! I again had some extra Cool Whip, because it didn't look very appealing after peeling the layer of foil from the cake. So I did a quick light layer to fancy up the cake. Then I just got creative and added some things that my daughter liked.....more Oreos, and sour gummy worms!