Prepare the dish: Spray a 9×13-inch baking dish with nonstick cooking spray and set aside.

Make the cookie crust:

Crush ginger snap cookies in a food processor.

Mix in melted butter and combine until evenly moistened.

Press half of the mixture firmly into the bottom of the baking dish as the base layer.

Pumpkin pudding layer:

In a large bowl, combine milk, pudding mix, pumpkin puree, and pumpkin pie spice.

Mix with a hand or stand mixer until thickened and smooth (about 2 minutes). Set aside.

Mousse layer:

In a separate bowl, beat cream cheese, powdered sugar, vanilla, and heavy cream until light and fluffy.

The mousse will double in volume. Set aside.

Whipped topping layer:

In another bowl, fold cinnamon into the thawed whipped topping. Set aside.

Assemble the layers:

Spread the pumpkin pudding layer over the cookie crust.

Add the mousse layer on top of the pudding layer.

Sprinkle the remaining cookie mixture over the mousse.

Spread the whipped topping layer over the top.

Drizzle generously with caramel topping.

Chill:

Cover and refrigerate for at least 6 to 8 hours, or overnight for best results.

Serve:

Top with additional caramel drizzle just before serving. Optional: sprinkle with extra cookie crumbs or cinnamon.