Heat Instant Pot by turning pressure cooker to saute function and waiting until it reads Hot.
Add in oil, small onion, green chiles, cumin and oregano and saute for 3-4 minutes, or until onion is softened. Turn Instant Pot OFF.
Pour in the chicken stock and scrape off any browned bits on bottom of Instant Pot.
Add cooked or canned white beans, and salt. Nestle chicken into liquid.
Close Instant Pot and be sure vent knob is sealed.
Cook on HIGH Pressure for 20 minutes if chicken is fresh, 25 minutes if chicken is frozen.
Once cook time elapses, let pressure release for at least 20 minutes.
Remove chicken from inner pot. Add in cream cheese to inner pot if using. Close lid on Instant Pot to keep the heat inside the chili--this will help melt the cream cheese.
Shred chicken and stir back into soup, stirring until cream cheese is well distributed through chili.
Serve with dollop of sour cream, shredded cheese, and cilantro.