Preheat oven to 375 degrees F. Spray a 9x13-inch baking dish with nonstick cooking spray; set aside. Cook ziti according to package directions then drain, rinse and set aside.

Heat olive oil in a large skillet over medium- high heat. Add turkey and onion and cook, breaking up meat, until meat is cooked through and onion is tender. Drain excess liquid then add Italian seasoning, water, diced tomatoes and marinara. Reduce heat to low and cook, stirring occasionally, for 10 minutes.

In a mixing bowl, combine ricotta cheese, parsley, egg, salt, pepper, 1 cup mozzarella and parmesan cheese.

Spread 1 cup of tomato sauce mixture in the bottom of the prepared pan. Top with half the ziti, all of the ricotta mixture and half the tomato sauce.

Top with remaining ziti, sauce and 1/4 cup mozzarella cheese. Bake for 25-30 minutes, or until top is lightly golden brown and cheese is melted