Prepare the pan. Wrap the bottom of a 7x3-inch springform pan with aluminum foil (optional, but allows for for easier transfer to a cake stand) then attach the sides of the pan. Use butter or non-stick spray to grease the sides. Set aside.
Make the crust. In a food processor, pulse the pecans into a fine crumble, then transfer to a medium mixing bowl. Add the graham cracker crumbs, brown sugar and cinnamon. Mix until well combined, then add the melted butter and continue to mix until the crumbs are evenly coated in butter.
Freeze the crust. Transfer the crust mixture to the prepared springform pan and spread it out in an even layer. Use a flat-bottomed cup to gently press and pack it down to ensure it's even across the bottom and the edges. Place in the freezer for 25 minutes.
Make the filling. In a large bowl, use a hand mixer on medium speed to beat the softened cream cheese, granulated sugar and brown sugar, until smooth. Add the pumpkin purée, heavy cream, vanilla, cornstarch, cinnamon, nutmeg, ginger and salt. Continue to mix on low-medium speed until smooth and creamy, scraping down the sides as needed.
Add the eggs. Add the room temperature eggs one at a time, mixing on low speed for no more than 10 seconds after each. Use a silicone spatula to gently fold the filling to ensure it's evenly mixed. Do not over mix at this step!
Assemble the cheesecake. Remove the crust from the freezer and pour the filling into the pan. Spread the filling out evenly, then gently tap the pan on the counter to encourage any large air bubbles to come to the surface to be popped. Cover the pan tightly with aluminum foil.
Make a sling. For easier removal from the Instant Pot, use a sling underneath the springform pan. Tear off a long length of foil and fold it into a 1.5-inch-wide strip.
Pressure cook. Pour in 1.5 cups of water into the Instant Pot insert, then add the trivet. Place the pan on top of the foil sling, then carefully lower the pan and sling onto the trivet. Tuck the ends of the sling over the foil cover. Close the lid, set the valve to sealing and pressure cook on Manual High pressure for 40 minutes (your Instant Pot model may have a "Pressure Cook" button rather than a "Manual" button). At the end of cooking time, allow pressure to release naturally for 20 minutes (the pin may drop before this, but let it sit).
Cool and chill. Use the sling to carefully lift the pan out of the Instant Pot and place it on a cooling rack. Uncover and let it cool to room temperature, for about an hour. Use a thin knife or offset spatula to scrape around the top edge (this will help prevent cracks as it cools and contracts further while in the refrigerator), then cover with cling wrap and place in the refrigerator overnight (minimum 6-8 hours).
Serve. While the cheesecake is cold from the fridge, gently unlatch and lift up the sides of the pan. Transfer the cake to a cake stand, if desired (see post for tips). For clean slices, run your knife under hot water and wipe clean between each cut. Serve with your favourite toppings. Store any leftovers covered in the refrigerator for up to 4 days.
To refrigerate: Cover the cake tightly with cling wrap, or slice and place in air tight containers, and put in the refrigerator. Eat within 4 days.
To freeze: Leave the cake on the bottom of the pan or transfer it to a cardboard round. Wrap it tightly with cling wrap, then foil, then place it in a freezer bag. For best results, freeze for no more than a month.
To thaw: Leaving the plastic wrap on, place the cheesecake in the refrigerator overnight. I like to bring it out of the refrigerator about 30 minutes before slicing and serving.
This recipe was tested in both a 6-quart and 8-quart Instant Pot models.