Prep the Fudge and Caramel: Microwave the hot fudge and caramel topping for 15-20 seconds to make them easier to spread.
First Layer: Line the bottom of a 9x13 baking dish with a layer of 10 ice cream sandwiches, trimming as needed to fit.
Kahlúa Drizzle: Pour the Kahlúa evenly over the ice cream sandwiches. Let it soak in for a minute or two.
Layer It Up: Spread half of the hot fudge, then half of the caramel, followed by half of the Cool Whip. Sprinkle on half of the chocolate chips and toffee pieces.
Repeat: Add another layer of ice cream sandwiches and repeat the Kahlúa drizzle and all the toppings.