Pour half of the salsa into the bottom of the pot. Arrange the chicken breasts on top of the salsa, at the bottom of the instant pot. Top with the rest of the salsa, black beans, kidney beans, corn, tomatoes, taco seasoning, and chicken broth.
Cook:
Put the lid on and seal the valve. Press the manual button and pressure cook on high for 20 minutes. It will take 6 to 8 minutes to come to pressure, then it will cook for 20.
When the timer goes off, release the pressure by opening the valve.
Using kitchen tongs, remove the chicken breasts onto a cutting board and shred them with two forks. Return them to the pot and combine the shredded chicken with the soup. You can also shred them inside the pot carefully so as not to burn yourself.
Serve:
Ladle the soup into bowls and top with sour cream, avocado, and cilantro.
Storage:
Once cooled, cover the pot with a silicone lid or transfer leftovers into an airtight container and refrigerate for up to 3 days.