Place half of your sandwiches in the bottom of a square serving dish . . . making sure sides of sandwiches are against the pan. I make it in a 9x13 glass dish.
Cover with whipped topping.
Top with half chopped walnuts.
Microwave 1/2 jar Chocolate syrup for 1-2 minutes, mix in 2 Tbls Kahlua.
Drizzle whipped topping with both chocolate and caramel.
Repeat above steps for next layer. Ending with whipped topping. Add Toffee Pieces to top.