Preheat the oven to 450°F. Coat a large baking sheet with non-stick cooking spray.

Blot the zucchini coins with paper towels to remove excess moisture. Place the zucchini in a medium bowl and drizzle with olive oil, turning to coat each piece. In a separate bowl, combine the Parmesan, bread crumbs, salt, and pepper.

Dip each zucchini coin into the Parmesan mixture, turning to coat and pressing the breading slightly to ensure it sticks. Place breaded zucchini coins in one even layer on the prepared baking sheet. Bake for 25 minutes or until browned and crisp.

Reduce the oven temperature to 400°F. Coat the bottom of a small baking dish with the marinara sauce. Layer one third of the crisp zucchini coins over marinara, overlapping if necessary. Sprinkle zucchini layer with mozzarella. Repeat the layers 3 times (or until the zucchini is gone, depending on the size of your baking dish) ending with a sprinkling of cheese.

Bake for 10-15 minutes or until the cheese is melted and the sauce is bubbling. Cool for 5 minutes before serving.