Meanwhile, in 12-inch skillet, cook beef and onion over medium heat 8 to 9 minutes, stirring occasionally, until brown; add garlic, and cook about 1 minute or until fragrant. Drain; return meat mixture to skillet. Over medium-low heat, stir in Italian seasoning, pepper flakes and salt. Add tomatoes, cooked pasta and 1/2 cup of the Parmesan cheese; cook 2 to 3 minutes, stirring constantly, until completely blended and heated through. Spoon mixture into baking dish; sprinkle with mozzarella cheese. Top with Alfredo sauce and remaining 1/2 cup shredded Parmesan cheese.