In a large skillet, cook the ground beef over medium-high heat until no longer pink. Drain the fat.

Add the onion and garlic to the skillet with the beef. Cook for 2-3 minutes until the onion becomes translucent and the garlic is fragrant.

Pour in the beef broth and bring to a boil. Stir in the elbow macaroni, then reduce the heat to medium-low. Cover and let it simmer, stirring occasionally, until the macaroni is cooked and the liquid is mostly absorbed, about 10-12 minutes.

Add the heavy whipping cream, sour cream, shredded sharp cheddar cheese, Dijon mustard, ketchup, salt, and black pepper to the skillet. Mix everything together until the cheese is melted and the sauce becomes creamy.

Remove the skillet from heat and let it rest for a couple of minutes to allow the flavors to blend together.