Add the chicken breasts, black beans, diced tomatoes, Ro-Tel, chicken broth, corn, chili powder, cumin, oregano, salt, and pepper to the Instant Pot inner liner. Do not stir excessively.
Secure the lid and set the vent to Sealing.
Select Manual/Pressure Cook (High Pressure) for 10 minutes.
When the cooking time finishes, allow a Natural Pressure Release (NPR) for 10 minutes, then carefully move the valve to Venting to release any remaining pressure (Quick Release).
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 well.
Ladle the soup into bowls and serve immediately with your desired toppings.
Notes
For a spicier soup, use the hot version of Ro-Tel or add 1/4 teaspoon of cayenne pepper with the other spices.
If you prefer a thicker soup, mix 1 tablespoon of cornstarch with 2 tablespoons of cold water and stir this slurry into the soup during the final simmer step.
If you do not have an Instant Pot, you can simmer this recipe on the stovetop for 25 minutes after bringing it to a boil.