
Heat the oil in a large pot or pan to medium heat. Add onion and peppers and cook 5 minutes to soften.
Add garlic and cook another minute, stirring.
Add ground beef. Cook for 5 minutes, stirring often, until the beef is cooked through. Drain excess fat if desired.
Add mustard, brown sugar, Worcestershire sauce, vinegar, chili powder, cayenne (if using), salt and pepper, tomato sauce, and hot sauce to taste. Stir and simmer at least 5 minutes to bring the flavors together. If your sauce is too thin, cook a bit longer to thicken. You can easily simmer longer to let the flavors develop even more.
Serve on your favorite buns!