Heat oil in a large Dutch oven over medium. Add onion and cook 3–4 minutes until soft, then add garlic and cook 30 seconds.
Add ground beef and brown, breaking it up with a spoon, about 6–8 minutes. Drain excess fat if needed.
Stir in tomato sauce, diced tomatoes, broth, Worcestershire, oregano, salt, and pepper. Bring to a simmer.
Add dry elbow macaroni, stir to combine, cover, and simmer 12–15 minutes until pasta is tender, stirring once or twice. Add a splash more broth if it gets too thick.
Remove from heat, stir in cheddar if using, and let sit 2 minutes to melt. Garnish with parsley and serve.