In a large Dutch oven or pot, brown the beef until no longer pink. If using a lean beef, you may need to add a tablespoon of olive to brown it.
Add the tomatoes, black beans, kidney beans, corn, tomato sauce, and taco seasoning. Stir to combine. Add beef broth or water to thin it out if desired. Bring to a boil, reduce heat to medium and simmer for 15-20 minutes to let flavors blend. Add salt and pepper to taste.
Top with sour cream, cheddar cheese, diced avocado, cilantro, or tortilla chips to serve. Store leftovers in the refrigerator.