Switch your pot on the saute setting, add the cooking oil and allow to heat.
Chop the chicken breast into large chunk, then add to the pot and cook until it loses the pink look, but is not fully cooked.
Sprinkle the taco seasoning over the chicken, then add the corn, beans, tomatoes, chilies, onion and garlic to the instant pot and mix well.
Put the lid on the instant pot and seal. Choose the manual setting and cook at high pressure for 15 minutes.
Once done, allow a natural release for 10 minutes, then do a quick release.
Open the lid and stir. Use 2 forks to shred the chicken, or simply break up the chicken chunks on the side of the pot with a wooden spoon.
Add your cilantro and sitr until combined.
Test for seasoning, and serve with sour cream, cheddar cheese and extra cilantro.