1. Bring a large pot of salted water to a boil. Cook the ziti until just shy of al dente (about 1–2 minutes less than package instructions). Drain and set aside.

2. In a large skillet, heat olive oil over medium heat. Add sausage and cook until browned, breaking it up with a spoon. Drain excess fat.

3. Add onions to the skillet and cook until soft, about 5 minutes. Stir in garlic and cook for 1 minute.

4. Stir in crushed tomatoes, tomato paste, Italian seasoning, and red pepper flakes. Simmer for 15–20 minutes. Season with salt and pepper.

5. In a medium bowl, combine ricotta, half the mozzarella, half the parmesan, and a pinch of salt and pepper.

6. Preheat oven to 375°F (190°C). In a bowl, toss the cooked pasta with most of the sauce, saving 1 cup for the top.

7. In a greased 9×13-inch baking dish, spread half the pasta mixture. Dollop with ricotta mixture. Add remaining pasta and top with reserved sauce.

8. Sprinkle with remaining mozzarella and parmesan.

9. Cover with foil and bake for 20 minutes. Uncover and bake another 10–15 minutes until bubbly and golden.

10. Let rest for 10 minutes before serving. Garnish with fresh basil or parsley.