Stir in the marinara sauce and Italian seasoning; simmer for 5 minutes to blend the flavors.
Combine ricotta cheese, half of the mozzarella, and Parmesan cheese; season with salt and pepper to taste.
Layer half the spaghetti, followed by the meat sauce, and then the ricotta mixture in a baking dish. Top with remaining spaghetti and mozzarella cheese.
Bake covered with foil for 25 minutes; then uncover and bake for an additional 10-15 minutes until cheese is bubbly and golden.
Garnish with fresh parsley before serving.
Notes
Make it personal by adding vegetables or spices. Can be assembled a day in advance.