Heat the oil in a large skillet over medium-high heat and brown the ground beef until no pink remains. Add the onions and cook until softened, about 5 minutes. Stir in the tomato paste, seasonings and flour. Pour in the milk and broth and stir. Stir in the macaroni. Bring to a boil then reduce to medium-low, cover and simmer for 10-12 minutes or until the macaroni is done. For al dente check after 9 minutes. Stir in the Cheddar cheese until melted.Serve immediately garnished with some chopped fresh parsley if desired.