Heat olive oil in a large pot over medium heat.
Add chopped onion and garlic. Sauté for 2–3 minutes until soft and fragrant.
Add the ground beef and cook until browned, breaking it up with a spoon.
Stir in tomato paste and mustard, cooking for 1 minute.
Add uncooked pasta, beef broth, and cream. Stir everything together.
Bring to a boil, then reduce heat to low. Cover and simmer for about 12–15 minutes, stirring occasionally, until pasta is cooked al dente.
Once pasta is cooked and most of the liquid is absorbed, stir in the grated cheddar cheese until melted and creamy.
Taste and season with salt and pepper as needed.
Serve hot, garnished with fresh parsley if using.