If using, place trivet in the Instant Pot insert and add water to it. Place the pumpkin on the trivet (or directly in the insert). Close the instant pot with vent in sealing position.
Set on MANUAL or pressure cook mode for 12 minutes. When the instant pot beeps, let the pressure release naturally.
Let the pumpkin cool a bit, then remove it carefully in a large plate or tray. Slice it in half. Using a spoon, remove the seeds.
Scoop the cooked pumpkin out from the skin. Add it to the food processor or blender. I had to add water to get a smooth texture. Adjust amount of water added to your preference.
Pumpkin Puree is ready. Use it or store in refrigerator or freezer.