Preheat oven to 350 F. Place a round piece of parchment paper in the bottom of a 9” springform pan to prevent sticking. Using your fingers, spread a tablespoon or two of plant butter around the edges of the pan to prevent sticking.
Pulse graham crackers and oats in a food processor until they become small crumbs. Transfer to a bowl and mix with coconut oil and plant butter. Press into the bottom of the springform pan (using the back of a spoon if needed) and refrigerate until ready to pour in the batter. No baking required!
The cashews need to be raw and soaked in boiling water for about 15 minutes to soften them. Drain the water and place cashews, vegan cream cheese, coconut cream + ½ cup reserved coconut water, vanilla sugar, vanilla, cornstarch, salt, pumpkin puree, cinnamon, ginger, nutmeg, and cloves together in a high-speed blender. Make sure to use the mixing wand and start at a low speed, slowly turning up. Once ingredients are incorporated, scrape down the sides and blend on high. If needed, add a few splashes of reserved coconut water to help thin out the batter (be careful not to add too much or the cheesecake will be soft, you need just enough to be able to blend the thick batter). Blend until very smooth, making sure the cashews are broken down and creamy.
Remove crust from the fridge and wrap a large piece of tin foil tightly around the outside of the cheesecake to prevent the water bath from getting into the cake. Pour in the batter and drop gently, a few times, on the counter to release the air bubbles. Smooth out the top with a spatula so that it looks pretty. Place the pan into a large baking dish and place on the middle shelf of a preheated oven. Carefully fill the dish with hot water until it comes halfway up the springform pan. Bake in the oven for 1½ hours, until the top is slightly browned and the cake is firm.
Once done, do not remove from the oven! Turn off the oven, crack the door open slightly and let cheesecake cool inside the oven for about 45 minutes. This also prevents the top from cracking as it cools. Transfer to the counter until cooled completely. Finally, tightly wrap and refrigerate overnight (at least 8 hours) or up to 6 days.
When ready to serve, run a sharp knife around outside of the cake, if needed. Gently remove outside ring of the springform pan, slice, and serve.