Prepare the ingredients: peel and cube 1/2 of a medium butternut squash; chop onion; and mince garlic.
Select "Saute" on the Instant Pot. Once the pot warms up, add onions and cook for ~3 minutes. Add salt and pepper. Add garlic and cook for ~1 minute.
Add ground beef and cook until the meat is browned, stirring every few minutes.
Add the cubed butternut squash and chili powder. Stir to combine.
Turn the Instant Pot "Off" briefly. Put the lid on a seal the Instant Pot, making sure that the valve is set to "Sealing."
Select "Beans/Chili" on the Instant Pot.
Let the pressure naturally release for 10-15 minutes. Release any additional pressure, if needed.
Top your chili with avocado and cilantro.