Add oil to your instapot and turn it to the saute setting. When the oil heats up, add the chicken breasts (whole) to the pot and sear both sides for about a minute
Turn the instapot off
In the instapot, add the crushed tomatoes, chicken broth, lime juice and seasonings. Stir to combine.
Cover the pot and secure the lid. Make sure the valve is set to sealing. Set the pressure cook button to 15 minutes and start it
Once completely cooked, vent and de-pressurize the instapot then open the lid. Shred the chicken with two forks or a hand mixer
Add the chicken back into the pot with the juices. Stir occasionally as the chicken absorbs the juices. Store the chicken in the fridge with the remaining juices or serve with the juices.