Combine the graham cracker crumbs, brown sugar, and melted butter in a mixing bowl. Stir with a fork to combine.
Remove the bottom of a 7-inch springform pan, wrap in parchment, and fit back into the pan.
Spoon the crust mixture into the pan, and use a flat-bottomed glass or measuring cup to press the mixture into the bottom.
Place the pan with crust into the freezer while you make the cheesecake batter.
In a large mixing bowl, beat the cream cheese, sour cream, and flour with a hand mixer for 30 seconds.
Add the sugar and vanilla extract, and mix well.
Add the eggs, and mix until just combined.
Add the pumpkin puree and pumpkin spice, and mix until combined.
Pour the cheesecake batter over the prepared crust.
Pour about 1 cup of water into the bottom of your Instant Pot, and then place the trivet on top. Carefully lower your cheesecake onto the trivet.
Lock the lid into place, and make sure the valve is set to “sealed.”
Select the Pressure Cooking option (Manual) and set the pressure to High. Set the timer for 30 minutes.
When the time is up, allow the pressure to release naturally. When the floating pressure indicator drops and the pressure has all released, carefully open the lid.
Use a paper towel to gently pat away any condensation from the top of the cheescake.
Allow the cheesecake to cool completely at room temperature, and then place it in the refrigerator to chill for at least 4 hours or overnight.
Serve with whipped cream or caramel sauce.