In a large pot or Dutch oven over medium heat, cook the ground beef and onion until the beef is no longer pink. Drain off any fat.
Add the green pepper, kidney beans, pinto beans, diced tomatoes, tomato sauce, chili powder, garlic powder, cumin, salt, black pepper, and cayenne pepper (if using). Stir to combine.
Bring the mixture to a boil, then reduce the heat to low and let simmer for 25-30 minutes, stirring occasionally.
Serve hot with desired toppings, such as shredded cheese, sour cream, diced onions, and/or chopped cilantro.
Interesting Facts
Chili is believed to have originated in the southwestern United States.
Chili is often served with tortilla chips or Fritos.
Chili is a popular topping for hot dogs and baked potatoes.