Line a 9x13 inch casserole dish with 12 of the ice cream bars. Cover with half of the whipped topping. Place the remaining 12 ice cream bars on top of the whipped topping. Top this layer of ice cream sandwiches with remaining whipped topping. Put in freezer until ready to serve.
Cut into squares to serve. (Top with chopped nuts and a drizzling of chocolate syrup, and a cherry, optional.)
Source: A friend, who is an excellent cook, served this dessert and everyone loved it. We all wanted the recipe, but figured it would be involved. What a pleasant surprise to find out how easy it is to make. Great for a last minute dessert. You can also make it ahead of time and keep it ready in the freezer.