For the crust, preheat oven to 300 degrees Fahrenheit and line a 9x13" cake pan with parchment paper so it comes over the sides. Stir together graham cracker crumbs, sugar, chopped pecans, and melted butter until fully combined. Press crust mixture onto the bottom of the parchment paper in the pan. Bake crust for about 25 minutes.
While crust is baking, prepare the filling by mixing together cream cheese, sour cream, sugar, vanilla, eggs, and canned pumpkin in the bowl of an electric mixer until combined well.
Remove crust from oven when done, sprinkle with 1/2 c. chocolate chips, then pour filling mixture over and spread evenly. Return to the oven and bake for approximately 50 minutes, or until set and not jiggly.
Let cool for one hour and then cover and place in the refrigerator overnight so the flavors can come together and filling can chill.
The next day, add the topping by drizzling with caramel sauce (as much as you want), then melted chocolate chips, then sprinkling with chopped pecans. Place in the refrigerator until ready to serve.