Arrange the eggplant rounds across a rack, distribute the 1-2 tablespoons salt over them, and leave for 1 hour. Small beads of moisture should collect on the cut surfaces.
Wash away the surface salt with water, then blot every slice thoroughly dry. The flesh should feel dry rather than slick before coating.
Set the oven to 400°F. A fully heated oven helps the breading begin setting when the baking sheet goes in.
Prepare the first dredging bowl with ¼ cup coconut flour. This dry coating forms the foundation beneath the egg.
Beat the 2 large eggs in a separate bowl for the middle coating station. The whites and yolks should blend into an even mixture.
Combine the almond flour, ½ cup Parmesan, Italian seasoning, garlic powder, and salt and pepper to taste in a third, shallow bowl. The seasonings and cheese should look evenly distributed throughout the crumbs.
Cover both faces of each round with coconut flour, pass it through the beaten eggs, and press on the almond flour mixture. A continuous coating should cling to the eggplant without thick, loose patches.
Transfer the breaded rounds to a baking sheet and cook for 25 minutes, flipping them halfway through. Look for a set exterior with golden color developing around the edges.
Cover the bottom of a 9x9-inch baking dish with ⅓ of the marinara. A thin, even layer gives the eggplant a sauced foundation.
Arrange a first layer of pre-baked eggplant over the sauce. The breaded rounds should form a distinct layer across the dish.
Distribute another ⅓ of the marinara across the eggplant and cover it with 6 mozzarella slices. The cheese should provide even coverage over the sauced rounds.
Build the next layer with the remaining eggplant, followed by the remaining marinara and final 6 mozzarella slices. The uppermost surface should be a cohesive cheese layer.
Return the assembled dish to the oven for 15-20 minutes. The casserole is ready when the mozzarella has melted completely.
Finish with the reserved Parmesan and freshly chopped parsley. The parsley adds green flecks against the melted cheese.