Combine all the ingredients except for toppings in the inner pot of a 6 or 8 quart Instant Pot. I have the 6 quart Duo. Stir gently to distribute the beans and spices.
Place the lid on the pot and turn to seal, making sure the silicone ring is in place. Turn the steam release handle on the top to "sealing" not "venting".
Press the "Pressure Cook" button until the mode says MORE. The other modes are LESS and NORMAL. Press the +/- button until the screen says 25. This sets the timer. Do nothing at this point and in about 10 seconds it will say "ON". It will display this for about 18 minutes while the inside of the pot comes up to pressure. Then, it will display 25 and start counting down in 1 minute increments.
After the 25 minutes of cooking time. For very soft beans, do nothing and the pressure will naturally release. This will take about 30 minutes. Or, if you prefer the texture similar to canned beans, naturally release the pressure for 15 minutes, then quick release it by turning the steam release handle from "sealing" to "venting". Be sure to keep hands and face away from steam as it releases.
Tip: If you have cabinets above your pressure cooker, you can divert the steam from going straight up by holding a kitchen towel over it at an angle.
Remove the lid when the float valve has dropped. You can shred the chicken right in the pot or remove it to a cutting board to shred or chop.
If you prefer a creamier texture, mash a few of the beans in the pot with a potato masher or large spoon.
Ladle the soup into bowls and add the toppings of your choice. Note: It thickens slightly in the fridge overnight.