Preheat your oven to 375°F (190°C).
Cook the rigatoni pasta according to package instructions until al dente. Drain and set aside.
In a large skillet, heat the olive oil over medium heat. Add the diced onion and cook until translucent, about 3-4 minutes.
Add the minced garlic and ground beef to the skillet. Cook until the beef is browned and cooked through, breaking it apart with a spoon, about 5-7 minutes.
Stir in the tomato sauce, diced tomatoes, oregano, basil, salt, and pepper. Let the mixture simmer for about 5 minutes.
In a large mixing bowl, combine the cooked rigatoni with the meat sauce. Stir until the pasta is well coated.
Transfer half of the pasta mixture to a greased 9x13 inch baking dish. Sprinkle half of the mozzarella cheese on top. Add the remaining pasta mixture and top with the rest of the mozzarella and the grated Parmesan cheese.
Cover the baking dish with aluminum foil and bake in the preheated oven for 20 minutes.
Remove the foil and bake for an additional 10-15 minutes, or until the cheese is bubbly and golden brown.
Let it cool for a few minutes before serving.