Preheat your oven to 375°F (190°C).
Cook the penne pasta according to the package instructions. Drain and set aside.
In a skillet, heat olive oil over medium heat. Add the diced onion and cook until translucent.
Add the minced garlic and cook for another minute.
Add the Italian sausage to the skillet and cook until browned. Break it into small pieces as it cooks.
Stir in the marinara sauce, dried oregano, and dried basil. Let it simmer for 10 minutes.
In a large bowl, combine the cooked penne pasta and the sausage mixture. Mix well.
Transfer half of the pasta mixture to a baking dish. Sprinkle half of the mozzarella and Parmesan cheese on top.
Add the remaining pasta mixture and top with the remaining cheese.
Bake in the preheated oven for 25-30 minutes, or until the cheese is melted and bubbly.
Let it cool for a few minutes before serving. Enjoy!