Add minced garlic and cook for 1 minute until fragrant. Press Cancel.
Place the chicken breasts into the Instant Pot liner.
Add the black beans, corn, diced tomatoes, Ro-Tel, chicken broth, chili powder, cumin, oregano, salt, and pepper over the chicken. Do not stir excessively.
Secure the lid and set the vent to Sealing.
Select the Manual or Pressure Cook setting on High Pressure for 10 minutes.
When the cooking cycle finishes, allow a Natural Pressure Release (NPR) for 10 minutes, then carefully move the valve to Venting to release any remaining pressure.
Open the lid. Remove the chicken breasts and place them on a cutting board.
Use two forks to shred the chicken. Return the shredded chicken to the soup. Stir everything together.
For best flavor, use fresh lime juice just before serving.
Serve this quick tortilla soup with crispy tortilla strips, shredded Monterey Jack cheese, diced avocado, and a dollop of sour cream.
If you prefer a thicker soup, mix 1 tablespoon of cornstarch with 2 tablespoons of cold water and stir into the simmering soup during the last 5 minutes.