I had this at a friends house and it was so good and as I found out so easy to make.
You will need a 9x13 pan, 24 ice cream sandwiches(any kind), 1 large tub cool whip, ice cream toppings, nuts, chocolate syrup, sprinkles, cherries, etc.
Layer 12 ice cream sandwiches in the bottom of the pan, cut them if you need to so they fit snuggly. Spread a layer of cool whip over that and then another layer of sandwiches followed by another layer of cool whip. Cover with foil tightly and freeze for several hours or overnight.
To serve: Take it out of the freezer and let it sit out for 5 minutes to soften, then add the toppings. You can go nuts here. I like to put chocolate syrup all over and then sprinkles followed by cherries with the stems so that everyone gets a cherry when you cut it. You just cut into squares and enjoy.
There are so many different kinds of ice cream sandwiches that you can have fun with. There are also low fat sandwiches making this a nice low fat dessert.