Preheat oven to 375°F (190°C). Grease a 9×13-inch baking dish and set aside.

Cook the ziti pasta in salted boiling water until al dente. Drain and set aside.

In a large skillet over medium heat, heat olive oil and cook the ground beef until browned. Add chopped onion and garlic, and cook until softened.

Stir in marinara sauce, basil, oregano, salt, and pepper. Simmer for 5–10 minutes.

In a medium bowl, mix ricotta cheese, egg, Parmesan cheese, and half of the mozzarella cheese.

In the prepared baking dish, spread a thin layer of meat sauce. Add half of the cooked ziti, then dollop and spread the ricotta mixture on top.

Layer with half of the remaining meat sauce, then the rest of the ziti, and top with the remaining meat sauce.

Sprinkle the remaining mozzarella cheese evenly over the top.

Cover with foil and bake for 25 minutes. Uncover and bake for an additional 10–15 minutes, until cheese is bubbly and lightly golden.

Let rest for 5–10 minutes before serving. Garnish with chopped parsley or basil, if desired.