Bring a large pot of salted water to a boil. Cook the pasta shells until just al dente according to the package directions. Drain and set aside.

Heat the olive oil in a large skillet over medium-high heat. Add the ground beef and onion. Cook for 6–7 minutes, breaking the beef into crumbles, until browned and the onion is tender. Drain excess grease if needed.

Stir in the garlic and tomato paste. Cook for about 1 minute, stirring frequently, until fragrant.

Pour in the tomato sauce and beef broth. Add the Italian seasoning, smoked paprika, salt, and black pepper. Stir well and bring the mixture to a gentle simmer.

Reduce the heat to medium-low and simmer for 5 minutes, allowing the sauce to thicken slightly.

Stir in the heavy cream until the sauce is smooth and creamy. Add the shredded cheddar and stir until completely melted.

Add the cooked pasta shells to the skillet and gently toss until evenly coated in the creamy beef sauce.

Cook for another 2–3 minutes over low heat, until everything is hot and the sauce clings to the shells. Serve warm.