01 -
Preheat oven to 350°F. Coat a 9×13-inch baking dish with nonstick spray and set aside.
02 -
Boil spaghetti noodles in salted water to al dente according to package instructions, then drain.
03 -
In a large skillet over medium-high heat, cook ground beef, diced onion, green bell pepper, Cajun seasoning, garlic powder, onion powder, and dried Italian seasoning. Break up beef and sauté until no longer pink and vegetables are tender, about 10 minutes.
04 -
Drain excess fat from skillet. Stir in marinara sauce, reduce heat to low, and simmer for 15 minutes, stirring occasionally.
05 -
In a large pot over medium heat, melt butter. Add minced garlic and sauté for 30 seconds until fragrant. Stir in heavy cream, shredded Parmesan, kosher salt, and black pepper. Cook, stirring, until cheese has melted and sauce thickens slightly.
06 -
Toss the cooked spaghetti in the Alfredo sauce until thoroughly coated. Spread evenly in the prepared baking dish.
07 -
Distribute the meat sauce evenly over the spaghetti in the baking dish.
08 -
Sprinkle shredded mozzarella and Parmesan cheese over the top. Bake uncovered for 15 minutes, until cheese is melted.
09 -
Optionally sprinkle with dried parsley flakes and serve hot.