Preheat the oven to 400F and line a large sheet pan with parchment paper.
Season the eggplant rounds with salt and pepper on both sides.
Prepare your station: in a shallow dish combine the flour with the garlic salt. In a second dish beat the eggs, and have a third dish with the breadcrumbs.
Dredge the eggplant into the flour to coat both sides, then dip into the beaten eggs, allowing the excess to drip off. Next, evenly coat each round with the panko breadcrumbs.
Lay the coated eggplant rounds into the prepared sheet pan and spray with cooking oil spray. Bake for 22-25 minutes, flipping halfway until eggplant is golden and crispy.
Meanwhile, in a large oven dish, spread 1/3 of the marinara sauce.
Once the baked eggplant is ready, arrange half of the rounds into the prepared baking dish.
Top with 1/3 of the marinara sauce, sprinkle with 1/2 of the mozzarella, and all the parmesan.
Repeat with the remaining ingredients, finishing with a layer of mozzarella.
Bake at 400F for 15 minutes, or until the cheese is bubbly.
Garnish with fresh chopped parsley.