On medium heat, heat oil in large skillet. Brown ground beef till it is no longer pink. Allow the onions to soften for five minutes. Stir in the tomato paste. Season with salt and flour. Stir in the milk mixture and broth. Add the macaroni.
Bring to a boil. Then reduce the heat to medium-low. Cover and let simmer for 10-12 mins or until the macaroni are done. For al dente check after 9 minutes.
Mix the Cheddar cheese with the milk until it is melted.
Sprinkle with some fresh parsley chopped on the side.