Step 1: Prepare the Pumpkin Mixture In a large mixing bowl, whisk together the pumpkin puree, instant vanilla pudding mix, cold milk, and pumpkin pie spice. Whisk for about two minutes until the mixture begins to thicken and the pudding mix is fully dissolved. Let it sit for five minutes to firm up.
Step 2: Fold in the Whipped Topping Gently fold in one cup of the whipped topping into the pumpkin mixture using a spatula. This lightens the texture into a fluffy mousse. Be careful not to over-mix, as you want to keep the air in the whipped topping. Keep the remaining whipped topping aside for the top layer.
Step 3: Begin Layering Place a few cubes of pound cake or gingerbread into the bottom of six individual clear glasses or small mason jars. Press them down slightly to create a solid base. Add a generous spoonful of the pumpkin mousse over the cake layer, smoothing it to the edges so the layer is visible.
Step 4: Add the Toffee and Repeat Sprinkle a teaspoon of toffee bits over the mousse. Add another layer of cake cubes, followed by another layer of pumpkin mousse. Continue this process until the glass is nearly full, leaving about half an inch at the top for the garnish.
Step 5: Garnish and Chill Top each cup with a dollop of the remaining whipped topping. Sprinkle more toffee bits on top and drizzle with a generous amount of caramel sauce. Refrigerate for at least one hour before serving to allow the cake to soften and the flavors to meld together perfectly.