In a large skillet add the beef and onions and cooking until beef is fully cooked. Remove beef from pan to drain and set aside.
In the same pan you just cooked the beef in, add the canola oil, red bell pepper, green bell pepper, corn and black beans and cook for, stirring often, until the bell peppers are soft.
Add in the cumin, water, boullion, tomato sauce, salsa, taco seasoning and ketchup. Cook at simmer for 5-6 until the sauce is thick.
Spoon the mixture on to the base of toasted buns. Sprinkle the shredded cheddar cheese over the beef mixture and place the top of the bun on. Makes 6-8 sloppy joes.