In a slow cooker, place the beef, onion, and bell pepper.
Add the tomato sauce, garlic powder, cumin, oregano, sea salt, and black pepper, and stir to combine.
Cover and cook on LOW for 6 hours, or on HIGH for 3 hours.
Before serving, taste to adjust salt and black pepper seasoning, if needed.
Serve the chili topped with the cheddar cheese and cilantro, if desired. Serve hot.