Preheat oven to 350°F.

Prepare the baking dish: Lightly grease an 8" x 8" high-sided baking dish or pan with softened butter or shortening. Measure and cut two strips of parchment paper that are 8-inches wide and about 15-inches long. Arrange the strips in the baking dish in a criss-cross pattern so that they cover the entire baking surface. Be sure that the ends are extended evenly so that they can serve as “handles” to remove the finished dessert from the dish before serving.

In a small bowl, combine the graham cracker crumbs, sugar and melted butter. The mixture is then pressed into the prepared baking dish. Do your best to distribute it evenly getting the mixture into all four corners. Set aside.

In a small bowl, use a hand mixer to beat the cream cheese, sour cream, granulated sugar and vanilla extract until smooth. Add the eggs, mix just until combined, then pour over the graham cracker crust.

Place in the preheated oven and bake for 20-25 minutes or until set. Transfer the dish or pan to a wire rack to cool.

In a medium saucepan set over medium-low heat, combine the egg yolks, pumpkin puree, brown sugar, milk, salt, pumpkin pie spice and cinnamon. Cook, whisking occasionally for about 10 minutes or until mixture reaches 160°. Remove from the heat and whisk in the vanilla extract.

In a small microwave-safe bowl, sprinkle the gelatin over the water. Let stand for 1 minute, then microwave for 30 seconds or until the gelatin is dissolved. Stir into the pumpkin mixture. Set aside.

In the top of a double boiler, combine the granulated sugar, egg whites and cream of tartar. Beat with an electric mixer set at low speed for 30 seconds, then set the pan over boiling water checking to be sure the pan isn’t touching the water.. Beat at high speed, for about 5 to 7 minutes, or until it's stiff and glossy. Remove it from the heat and beat an additional 1 to 2 minutes.

Fold the egg white mixture into the pumpkin mixture then spread that combination evenly over the cheesecake layer.

Refrigerate uncovered for 1 hour. Then cover and refrigerate for an additional 3 hours or until firm.

When ready to serve: Remove from the fridge. Grab the ends of the bottom layer of parchment paper and lift the entire dessert onto a cutting board. For large servings, cut into nine equal squares. For smaller servings, cut into sixteen squares. Top each square with whipped cream and a dusting of pumpkin pie spice. Or graham cracker crumbs.