Prep Ingredients: Dice the onion, mince the garlic, and drain the beans.
Sauté in Instant Pot: Set the Instant Pot to "Sauté." Add a bit of oil, then cook the onions and garlic for 2-3 minutes until softened.
Add Chicken & Seasoning: Add the chicken, beans, chilies, broth, cumin, chili powder, oregano, garlic powder, salt, and pepper.
Cook on High Pressure: Seal the lid, set the Instant Pot to "Manual" or "Pressure Cook" on high for 15 minutes.
Quick Release: Once the timer goes off, perform a quick release to release the pressure.
Shred Chicken: Remove the chicken, shred it with two forks, then return it to the pot.
Finish the Chili: Stir in sour cream and heavy cream. Let it simmer for another 5 minutes.
Serve: Ladle the chili into bowls and garnish with cheese or avocado if desired.