Preheat the oven to 350°F/180°C.
To make the crust, in a food processor break down the graham crackers to create crumbs.
In a bowl combine the graham cracker crumbs with sugar and butter.
Press into a 9-inch springform pan, with about ½ inch on the sides up. Bake for 8 minutes, then cool on a wire rack.
Wrap the springform pan with two layers of foil from the outside.
Boil water for the water bath, this will help the cheesecake not crack. See note 2
Keep your oven temperature the same.
In a large bowl, heat the cream cheese with the sugars until creamy and well combined (about 4 minutes).
Add in the eggs, vanilla, pumpkin spice, pumpkin puree, sour cream and salt- beat until combined scraping down the sides as needed.
Pour the mixture into the pre-baked graham crust, place the pan into a larger pan and add the water into the larger pan to create a water bath.
Bake for one hour until the cheesecake sets at the edges, and the center is not very jiggly (it will still have a little jiggle).
Switch off the oven, open the oven door slightly and let the cheesecake rest in the oven until the oven cools down (about 45 minutes to one hour).
Remove the cheesecake from the water bath, cover with plastic wrap and let it cool down completely then chill in the fridge until it has been fully chilled and set, minimum 4 hours but preferably overnight. To release the cheesecake run a knife around the edges and release from the pan.
To make the whipped cream, in a cold bowl, combine all of the ingredients and beat on high speed until fluffy (do not over beat, takes about one and half minutes). Top the cheesecake with whipped cream, and sprinkle with ground cinnamon or pumpkin pie spice.