Wash and slice the eggplants into 1/4-inch rounds, sprinkle salt on each slice, and let them sit for 45 minutes to 1 hour. Pat them dry after.

Heat ½ cup of olive oil in a large skillet. Fry eggplant slices in batches for about 2 minutes on each side until soft and golden brown, then transfer to paper towels.

In the same skillet, add oil if needed, sauté finely chopped onion and rubbed garlic until caramelized (5-7 minutes). Stir in diced tomatoes, basil, herbs, black pepper, and remaining salt. Simmer for 20 minutes.

Preheat oven to 350°F (180°C). In a greased dish, layer eggplant, sauce, and sprinkle Parmesan and mozzarella. Repeat, finishing with sauce and cheese, topping with breadcrumbs.

Bake for 40 minutes until bubbly and golden. Broil for an additional 2 minutes to crisp the top. Let cool for 15 minutes before serving.