Cut 2 large eggplants into 1/4″ lengthwise slices. Place in one layer on a colander. Sprinkle kosher salt liberally over both sides. Place a bowl on top and put 2 full cans of something to weight down the bowl so eggplant slices will release bitterness and moisture. Thanks Lidia B. After at least 20 minutes, rinse the slices and place on paper towels and dry both sides. Slice 4 zucchini into same thickness as eggplant, lengthwise. All slices should be flat on both sides. Season with garlic powder, ground black pepper, pepperoncini to taste.
Dredge both eggplant and zucchini slices in panko crumbs. In a large skillet, add a little olive oil and brown all slices on both sides in stages and set aside on a paper towel. Slice 2 large heirloom tomatoes. Slice your favorite combination of cheeses. Fontina. Parmesan. Asiago. Whatever you have in the fridge that complements the vegetables and each other.
In a small baking dish, drizzle a little olive oil on the bottom. Add half the slices of zucchini, eggplant, tomatoes, cheese. Repeat another layer. End with tomatoes on top and sprinkle with grated cheese. Drizzle olive oil on top.
In a preheated 400 degree oven, bake for 30 minutes. Turn oven off. Keep dish in for another 30 minutes. Take out of oven and let cool. Refrigerate. Best next day.