Preheat your oven to 350°F (177°C) and coat a 9x13-inch baking dish with nonstick spray.

Heat 2 tablespoons of olive oil in a large skillet over medium heat. Add 1 chopped onion and 1 diced green bell pepper. Sauté for 5-7 minutes until softened.

Add 4 minced garlic cloves to the skillet and sauté for another 1-2 minutes until fragrant.

Add 1 pound of ground beef, breaking it apart, and cook for 7-10 minutes until browned. Drain excess grease.

Stir in 1 teaspoon of salt, ½ teaspoon of black pepper, and 1 tablespoon of Italian seasoning. Add 1 ½ jars (36 ounces) of spaghetti sauce and let simmer for 5 minutes.

Bring a large pot of salted water to a boil. Cook 16 ounces of spaghetti according to package directions (8-10 minutes). Drain and set aside.

In a separate pan, melt ½ cup of butter. Add 4 minced garlic cloves and sauté for about 1 minute. Whisk in ½ cup of all-purpose flour, cooking until bubbly.

Slowly add 2 cups of heavy cream, stirring until smooth. Gradually whisk in 1 ½ cups of Parmesan cheese until melted and creamy.

Toss the drained spaghetti into the Alfredo sauce, ensuring each strand is coated. Spread into the greased baking dish.

Spoon the meat and red sauce mixture over the spaghetti without mixing the layers.

Sprinkle 2 cups of shredded mozzarella cheese over the top of the casserole.

Bake uncovered for about 30 minutes until bubbling and cheese is melted.

Let cool for about 10 minutes before serving. Optionally garnish with parsley and extra Italian seasoning.