Cook the macaroni according to package instructions.
In a large skillet over medium heat, brown the ground beef.
Add the diced onion and garlic to the skillet and sauté until translucent.
Stir in the ketchup, mustard, beef broth, and season with salt and pepper.
Bring the mixture to a simmer, then reduce heat and stir in the heavy cream.
Add the cooked macaroni and shredded cheddar cheese, stirring until well combined.
Serve hot, garnished with chopped parsley.