Bring a large pot of salted water to a boil and cook the pasta shells according to package instructions. Drain and set aside.
Heat olive oil in a large skillet over medium heat. Add ground beef and cook until browned, breaking it apart as it cooks.
Add the diced onion and cook for about 3 minutes until softened. Stir in the minced garlic and cook for another 30 seconds.
Pour in the tomato sauce and beef broth, then add Italian seasoning, paprika, salt, and black pepper. Stir well.
Let the mixture simmer for about 5 minutes so the flavors combine.
Stir in the heavy cream and mix until the sauce becomes smooth and creamy.
Add the cooked pasta shells to the skillet and toss to coat them in the sauce.
Stir in the shredded cheddar cheese and Parmesan cheese until melted and creamy.
Garnish with fresh parsley and serve warm.