Add the chopped onion to the pot and cook until softened, about 3 minutes.
Stir in the minced garlic and cook for 1 minute more until fragrant.
Add the crushed tomatoes, Rotel, beef broth, kidney beans, and black beans. Stir well.
Stir in the chili powder, cumin, oregano, salt, and pepper.
Secure the lid on the Instant Pot and set the vent to Sealing.
Cook on Manual/Pressure Cook setting on High Pressure for 15 minutes.
Once cooking is complete, allow a Natural Pressure Release (NPR) for 10 minutes, then carefully perform a Quick Release (QR) for any remaining pressure.
Stir the chili well before serving.
Notes
Serve with your favorite toppings like shredded cheese or sour cream.
You can adjust the spice level by adding cayenne pepper to your taste.