Start by setting your Instant Pot to the 'Sauté' mode. Add the canola or vegetable oil. Once hot, add the diced onion and sauté for about 3-4 minutes until it becomes translucent. Stir in the minced garlic and cook for an additional 30 seconds until fragrant.
Add the ground beef or chicken to the pot. Break it apart with a spatula and cook until browned, about 5-7 minutes. Make sure to stir occasionally to ensure even cooking.
Once the meat is browned, add the crushed or diced tomatoes, tomato sauce, diced green chiles, black beans, red beans, green bell pepper, taco seasoning, dried oregano, and red pepper flakes. Stir everything together until well combined.
Pour in the low sodium beef broth. If you prefer a thicker soup, you can use only 3 cups of broth. Stir to combine all the ingredients.
Close the lid of your Instant Pot, making sure the valve is set to 'Sealing'. Set the pot to 'Manual' or 'Pressure Cook' for 10 minutes at high pressure. Once the cooking time is complete, allow for a natural release for 10 minutes before performing a quick release for any remaining pressure.
In a small bowl, mix the cornstarch with the water to create a slurry. Once the pressure has been released, open the lid and stir in the cornstarch mixture. Set the Instant Pot back to 'Sauté' mode and let it simmer for a few minutes until the soup thickens to your desired consistency.
Taste the soup and add salt and pepper as needed. Adjust the seasoning based on your preference for heat and flavor.
Ladle the soup into bowls and garnish with chopped cilantro, crumbled Cotija cheese, diced avocado, and sliced jalapeno peppers. Serve with tortilla chips on the side for crunch.