Sauté veggies. Heat oil in a large skillet over medium heat. Add onion and bell pepper and cook 4 to 5 minutes until softened. Add garlic and cook 30 seconds.
Brown the meat. Add ground beef. Cook 6 to 8 minutes, breaking it up, until browned. Drain excess fat if needed.
Cook tomato paste. Stir in tomato paste and cook 1 minute.
Make the sauce. Stir in ketchup, tomato sauce, Worcestershire, mustard, brown sugar, vinegar, paprika, salt, and pepper.
Simmer. Reduce heat to low and simmer 8 to 10 minutes, stirring occasionally, until thick and glossy. Add a splash of water or broth if it gets too thick.
Serve. Spoon onto toasted buns. Add pickles or cheese if you want, and serve immediately.
