In a pan, brown the beef. Then, add the onion till fragrant. Add 1 tablespoon of taco seasoning. Mix well to combine. Transfer the seasoned beef to the crock pot.
Add chili beans, tomato sauce, water and diced tomatoes. Add the rest of the taco seasoning. Cook in crock pot for 4 hrs high or 6-8 hours in low. Add salt and pepper if needed. Season to taste only. Sprinkle extra cheese and sour cream before serving. Enjoy!