Making Baked Ziti is straightforward if you follow these clear steps:

1. Preheat Oven: Begin by preheating your oven to 375°F (190°C).
2. Cook Pasta: In a large pot of boiling salted water, cook the ziti or penne according to package instructions until al dente. Drain and set aside.
3. Sauté Meat and Veggies: In a large skillet, heat olive oil over medium heat. Add diced onion and cook until translucent. If using, add ground beef or Italian sausage and cook until browned, breaking it into smaller pieces. Add minced garlic, cooking for an additional minute.
4. Add Sauce: Pour marinara sauce into the skillet, stirring to combine. Let simmer for about 5 minutes. Season with salt and pepper to taste.
5. Prepare Cheese Mixture: In a bowl, combine ricotta cheese, egg, oregano, and basil. Mix until smooth and set aside.
6. Combine Ingredients: In a large mixing bowl, combine cooked pasta with the marinara sauce mixture, making sure the pasta is well-coated.
7. Assemble Ziti: In a greased 9×13 inch baking dish, spread half of the pasta mixture. Add dollops of the ricotta mixture on top, followed by half of the mozzarella cheese. Repeat the layering process with the remaining pasta, ricotta, and mozzarella.
8. Top with Parmesan: Sprinkle grated Parmesan cheese evenly over the top layer of cheese.
9. Bake: Cover the baking dish with aluminum foil and bake in the preheated oven for 25 minutes. Then, remove the foil and bake for an additional 15-20 minutes or until the top is bubbly and golden brown.
10. Cool and Serve: Once done, let the Baked Ziti cool for about 10 minutes before slicing. Garnish with fresh basil or parsley, if desired.

These straightforward steps will have you enjoying this incredible dish in no time!