Spray a 7x3 springform pan with a nonstick cooking spray.
MAKE CRUST:
In a food processor pulse the pecans until they are very fine and transfer them to a small bowl.
Add the graham cracker crumbs, melted butter, brown sugar, and cinnamon, and mix until the mixture is coated with butter and looks like wet sand.
Pour the mixture into the springform pan and smooth into an even layer.
Use a measuring cup or glass with a flat bottom to pack it down and make it more even.
Place the springform pan in the freezer for 25 minutes.
MAKE PUMPKIN CHEESECAKE FILLING:
While the crust is freezing, beat the softened cream cheese and sugars together at medium speed in a stand mixer fitted with a paddle attachment or in a large bowl using a hand mixer.
Then add the remaining ingredients and beat until smooth. Scrape down the sides of the bowl as needed to ensure everything is well combined.
PREP PAN WITH FOIL:
Remove the springform pan from the freezer and pre-fit a “lid” with tinfoil. Have the foil loose at the top in case the cheesecake rises to touch it, but tight along the sides. Set this aside.
FILL PAN AND COOK:
Pour the cheesecake filling into the springform pan ensuring your mixture leaves about ¼ inch at the top, and then place the tin foil “lid” on top.
Add 1 ½ cups of water to the Instant Pot, the trivet, and then the springform pan (gently) and secure the Instant Pot lid with the valve in the “Sealed” position.
In manual mode set the timers to 40 minutes on high if you have the option and press start. When the machine is done allow the pressure to release naturally for 25 minutes before opening the lid and removing the cheesecake.
COOL AND CHILL CHEESECAKE:
Place the cheesecake on a cooling rack and remove the tin foil.
Cool for about an hour and then run a knife around the outer edge. (The center may look a little jiggly, but it will solidify as it cools. If it does not, you can put it back in the Instant Pot for 10 minutes with another 10-minute natural release before opening the lid).
Move the cheesecake to the fridge and allow it to chill overnight or at least 6 hours before removing it from the springform pan.
SERVE:
Serve as is or top with whipped cream, caramel drizzle, or chocolate drizzle.
Notes
The cheesecake should be stored in an airtight container and kept refrigerated.