Place the chicken ingredients in the pressure cooker pot. Arrange the chicken so it is in a flat layer on the bottom of the pot as much as possible.
Secure the lid and turn pressure release knob to a sealed position. Cook at high pressure for 12 minutes.
When cooking is complete, use a 10 minute natural release, then release any remaining pressure.
Set chicken on a plate and shred or slice into strips. Drizzle with some of the juices from the pot.
Place peppers and onions into the pot and toss in the juices. Secure the lid and turn pressure release knob to a sealed position. Cook at high pressure for 2 minutes.
When cooking is complete, use a quick release.
To serve, place a few slices of chicken on a warm tortilla, top with peppers, onions, and other desired toppings like guacamole, sour cream, and salsa.
