Creating the Creamy Southern Spaghetti Bake is simple when you follow these straightforward steps:

1. Preheat Oven: Preheat your oven to 350°F (175°C).
2. Cook Spaghetti: Boil a large pot of salted water and cook the spaghetti according to package instructions until al dente. Drain and set aside.
3. Brown the Meat: In a large skillet, over medium heat, add the ground beef or Italian sausage. Cook until browned, then drain excess fat.
4. Add Aromatics: Stir in the diced onion and minced garlic. Cook until the onion is translucent and fragrant, about 3-5 minutes.
5. Mix in Tomatoes: Add the diced tomatoes, tomato sauce, Italian seasoning, and Worcestershire sauce. Stir to combine and let it simmer for about 10 minutes.
6. Incorporate Cream: Reduce heat and stir in the heavy cream. Mix until fully combined and heated through. Season with salt and pepper to taste.
7. Combine with Spaghetti: In a large bowl, combine the cooked spaghetti with the sauce mixture until the pasta is well coated.
8. Layer in Dish: Transfer half of the spaghetti mixture into a greased 9×13-inch baking dish. Sprinkle half of the mozzarella cheese on top.
9. Add Another Layer: Pour the remaining spaghetti mixture over the cheese layer. Top with the remaining mozzarella and all of the Parmesan cheese.
10. Bake: Place the dish in the preheated oven and bake for 30-40 minutes, or until the cheese is bubbly and golden.
11. Rest: Once baked, remove from the oven and let it rest for about 10 minutes before serving.

These steps make it easy to enjoy this incredible dish that combines rich flavors and cheesy goodness effortlessly!