In a large skillet or Dutch oven, cook the ground beef and chopped onion over medium-high heat until the beef is browned and the onion is translucent. Drain off any excess fat.
Stir in the tomato paste, beef broth, chili powder, garlic powder, and parsley flakes until well combined.
Bring the mixture to a boil over medium heat, then stir in the uncooked elbow macaroni.
Reduce the heat to medium, cover, and simmer for 10-12 minutes, stirring occasionally, until the pasta is al dente.
Reduce the heat to low, then stir in the freshly shredded cheese one handful at a time until melted and creamy.
Season with salt and black pepper to taste. Let cool 5-10 minutes before serving.