Preheat the oven to 325 degrees F. In a medium bowl, stir together 1 cup flour, 1/2 cup butter (melted), 1/2 cup finely chopped pecan, 1 tsp cinnamon, and 1/2 tsp nutmeg. Press into a greased 9x13-inch pan. Bake uncovered for 25 minutes. Cool completely.

In a small mixing bowl, blend together 8 oz cream cheese, 1 cup of powdered sugar, and 2 cups of whipped topping. Mix well and pour into the cooled crust.

In a medium mixing bowl, blend together pumpkin puree, 3 small boxes of instant vanilla pudding, 2 cups of milk, 1 tsp of cinnamon, and 1/2 tsp nutmeg. Blend well then chill until firm, about 10 minutes. Add 1 cup of whipped topping and blend until thick and smooth. Spread over the cream cheese layer.

Top with remaining whipped topping. Garnish with 1/2 cup chopped pecans, if desired. Chill overnight before serving.