Preheat oven to 375°F (190°C) and grease a casserole dish.
Cook pasta shells according to package instructions and drain.
Heat olive oil in a skillet over medium heat.
Add diced onion and cook until soft.
Stir in minced garlic and cook for about 30 seconds.
Add ground beef and cook until browned breaking it apart as it cooks.
Stir in marinara sauce, heavy cream, Italian seasoning, paprika, salt, and black pepper.
Add cooked pasta shells and mix until well combined.
Transfer the mixture into the prepared casserole dish.
Sprinkle cheddar, mozzarella, and parmesan cheese evenly over the top.
Bake for 20–25 minutes until the cheese melts and becomes bubbly.
Garnish with chopped parsley before serving.
