Preheat oven to 350°F Coat a 9 X 13-inch baking dish with cooking spray; set aside.
Combine bread crumbs, Parmesan cheese, Italian seasoning and garlic powder in a medium-size bowl; set aside. Remove skin from eggplant and trim off ends; slice eggplant into 1/2-inch-thick slices.
Dip eggplant first into egg whites and then into bread crumb mixture. Bake eggplant on a nonstick cookie sheet until lightly browned, about 20 to 25 minutes, flipping once.
Place a layer of eggplant on bottom of prepared baking dish, then add 1/3 of tomato sauce and 1/3 of mozzarella cheese. Repeat with 2 more layers in same order. Bake until cheese is melted and sauce is bubbling, about 10 minutes more. Slice into 4 pieces and serve.