Close the lid. Set Instant Pot to 5 minutes at high pressure. At the end of the cooking time, allow the pot to rest undisturbed for 10 minutes and then release all remaining pressure.
Shred the chicken and put it back into the stock in the pot. You can remove it as needed to make tacos with the remaining sliced onions, tomatoes, arugula or romaine or eat with the broth over rice or cauliflower rice.