Preheat your oven to 400°F. This is an important first step to ensure your Baked Ziti comes out perfectly baked and bubbly. Lightly oil a 9 X 13-inch baking dish to prevent sticking.
In a large Dutch oven or saucepan, add the sweet Italian ground sausage. Cook over medium-high heat, using a wooden spoon to break it up. Keep cooking until it’s no longer pink, which should take about 10 minutes. Once done, use a slotted spoon to transfer the sausage to a plate, leaving the drippings in the pot.
To the same saucepan, heat the olive oil. Add in the chopped onion and garlic, cooking and stirring occasionally until they’re soft and fragrant, about 3 to 5 minutes. This step is crucial, as the aroma will fill your kitchen and set the stage for the rest of the dish. Next, stir in the tomato paste and continue cooking for another 1 to 2 minutes.
Now, it’s time to add the main component of our sauce: the whole peeled San Marzano tomatoes. Use your fingers to break them into smaller chunks directly into the pot. Add the tomatoes along with their purée, dried oregano, and the reserved sausage. Bring the mixture to a boil, then reduce the heat to medium-low. Allow it to simmer until thickened, which should take about 20 minutes.
While the sauce is simmering, bring a large pot of salted water to a boil over high heat. Add the ziti and stir occasionally until the water returns to a boil. Cook the pasta for 2 minutes less than the package directions. The ziti should still be firm as it will finish cooking in the oven. After draining, remember not to rinse the pasta; you want to keep that starch!
Once the pasta is cooked, add the ziti and ricotta cheese to the sauce mixture. Stir gently until everything is well combined. This step ensures that each piece of pasta is coated with that delectable sauce.
Spread half of the pasta mixture into the prepared baking dish. Now, sprinkle half of the mozzarella or provolone cheese over the top. This layer of cheese is where the magic starts!
Next, top with the remaining pasta mixture. Sprinkle with the grated Parmesan cheese and the rest of the mozzarella or provolone cheese. The more cheese, the better!
Finally, bake your Baked Ziti in the preheated oven until the cheese is golden and the sauce is bubbly, about 20 to 25 minutes. The smell will be incredible! Once it’s done, let it stand for about 5 minutes before serving to allow all the flavors to meld.