In a large mixing bowl, cream together cream cheese and powdered sugar until smooth and fully blended. Blend for 1-2 minutes until there are no lumps.
Fold in 1 tub of whipped topping, chocolate sauce, and peanut butter. Blend for about 2 minutes until fully combined. The mixture will be a light shade of brown.
Fold in the chopped Reese minis. Use a rubber spatula to toss and combine fully. Be sure to scrape the edges of the bowl while doing so.
In the bottom of a 9x13 baking dish, lay the first layer of ice cream sandwiches flat, flush, and side by side with one another. You may have to cut an ice cream sandwich in half so that it covers the bottom of the dish evenly.
Pour the mixture over ice cream sandwiches and spread evenly using a rubber spatula.
Top with remaining ice cream sandwiches, covering the Reese mixture and repeating the same pattern as the first layer.
Add the final tub of whipped topping over the ice cream sandwiches and spread evenly with the rubber spatula.
Cover and place inside the freezer for 6 hours or overnight before serving.
When ready to serve, garnish the cake with additional chocolate sauce drizzles, whole Reese's cups (cut in half or broken up), and Reese’s Pieces (whole and crushed). Cut with a knife or metal spatula to serve.