Preheat the oven to 375°F (190°C). Lightly grease a 2-quart baking dish with nonstick spray.
Bring a large pot of salted water to a boil. Cook the ziti 1 to 2 minutes less than the package directions so it remains slightly firm. Drain the pasta and set it aside.
In a large bowl, combine 1 1/2 cups (360ml) of the pasta sauce, cottage cheese, cooked ground meat, 1 cup (115g) of the mozzarella cheese, egg, Italian seasoning, minced garlic, and black pepper.
Add the drained ziti to the bowl and stir well to coat the pasta evenly.
Spread 1/2 cup (120ml) of the remaining pasta sauce on the bottom of the prepared baking dish. Pour the pasta mixture over the sauce in an even layer.
Top the pasta with the last 1/2 cup (120ml) of pasta sauce, the remaining 1/2 cup (55g) of mozzarella cheese, and the Parmesan cheese.
Cover the dish tightly with aluminum foil. Bake for 45 to 50 minutes. The center of the casserole must reach a safe internal temperature of 160°F (71°C) to ensure the egg and meat are fully heated.
Remove the foil and bake for another 10 minutes until the cheese is melted and lightly browned. Let the dish rest for 5 minutes before serving.