01 - Preheat oven to 375°F and grease a 9x13-inch baking dish.
02 - Boil salted water and cook pasta until just al dente. Drain and set aside.
03 - Heat olive oil in a skillet over medium heat. Cook onion until translucent, about 3 minutes. Add garlic and cook 1 minute more.
04 - Add ground beef to skillet, breaking it up, and cook until browned and no longer pink, about 6 to 8 minutes. Drain excess fat.
05 - Stir marinara sauce, Italian herbs, salt, pepper, and optional red pepper flakes into the beef. Simmer for 5 minutes.
06 - In a large bowl, mix cooked pasta with half the meat sauce, ricotta cheese, and 1 cup mozzarella cheese gently to combine.
07 - Pour half the pasta mixture into the baking dish. Top with half the remaining sauce and half the Parmesan. Repeat layers with remaining mixture, sauce, mozzarella, and Parmesan.
08 - Cover with foil and bake 25 minutes. Remove foil and bake an additional 10 to 15 minutes until cheese is bubbly and golden.
09 - Let rest for 10 minutes before serving; garnish with fresh basil if desired.