Line a 9x9-inch pan with parchment paper, leaving an overhang for easy removal. If ice cream is super firm, let stand at room temp for 5 minutes; don’t let it get too soft!
Unwrap the ice cream sandwiches. Press 9 sandwiches onto the bottom of the pan. You’ll need to cut 2 down a little for them to fit (see pictures in the post).
With a large spoon, spread half the ice cream over the ice cream sandwiches. Press down as much as you can to an even layer.
Firmly press 9 more sandwiches on top. Spread remaining ice cream over the sandwiches, pressing firmly down. Cover tightly and place in the freezer until layers are firm, about 1 hour.
Remove the dessert from the freezer and spread the whipped topping over everything. Crush Oreos and sprinkle on top. Return to freezer, covered gently until very firm.
Use parchment paper overhang to remove bars from pan. Cut and serve. To get clean slices, run your knife under hot water for a few seconds, wipe to dry, make 1 slice, and repeat.
Immediately return any leftovers, covered tightly, to the freezer.
Video
Notes
Note 1: Other toppings: Try a crushed candy bar (Heath, Skor, Butterfinger, etc) instead of the cookies if desired.Storage: Store leftover Ice Cream Sandwich Cake in an airtight container in the freezer; best enjoyed within 2 weeks.