1. Bring a large pot of salted water to a boil. Add spaghetti and cook until al dente. Drain and set aside.

2. In a cast iron skillet, brown ground beef over medium-high heat until fully cooked.

3. Add chopped onion and garlic to the skillet and sauté until softened, about 3 minutes.

4. Stir in Cajun seasoning and cook for another minute to develop flavor.

5. Reduce heat to medium. Add heavy cream and cream cheese to the skillet and stir until smooth and melted.

6. Gradually add cheddar, mozzarella, and Parmesan cheese. Stir continuously until sauce is smooth and creamy.

7. Season with salt and black pepper.

8. Add the cooked spaghetti into the skillet and toss to coat with the sauce.

9. Spread the beef mixture evenly over the top of the pasta.

10. Sprinkle additional cheese if desired.

11. Place skillet under broiler for 3–5 minutes until cheese is bubbly and lightly browned.

12. Garnish with fresh parsley and serve hot.