Preheat oven to 350 degrees F. Line an 8" or 9" square baking pan with aluminum foil. Set aside.
make the crust:
In a medium mixing bowl, stir with a fork graham cracker crumbs, sugar and melted butter. Sprinkle into an even layer onto the bottom of a prepared baking pan. With a flat-bottom glass, press the crust down. Bake in the oven for 7 minutes then cool completely.
make the cheesecake layer:
In a medium mixing bowl, mix with a hand mixer softened cream cheese for 30 seconds. Add powdered sugar and mix in well. Add whipped topping and mix just until incorporated. Spread the mixture over cooled crust. Smooth out with an offset spatula.
make pumpkin layer:
In a medium mixing bowl, whisk pudding mix with half and half until thick. Add pumpkin puree and spice and mix until well incorporated. Spread over cheesecake layer. Smooth out with an offset spatula.
Top the pumpkin layer with remaining amount of whipped topping. Place in the fridge and chill for at least 4 hours, preferably overnight.
To serve:
Sprinkle chopped nuts over the dessert. Cut into 9 generous size squares, wiping the knife clean after each cut. You can also drizzle caramel sauce over each slice.
Notes
Half and half can be found in the dairy section in any grocery store. It's a mixture of even amounts of whole milk and light cream. I highly recommend using half and half in this recipe as it helps keep the pumpkin layer stable and the slices cut clean.