Preheat the oven to 350°F. Line a large baking sheet with parchment paper and grease with a little olive oil.
Slice the eggplants into ¼-inch rounds.
Mix the panko crumbs with the thyme, oregano, salt, and pepper. Whisk the eggs together in a bowl.
Dip the eggplant rounds one at a time into the eggs, letting any excess drip off, then into the panko mixture until well coated.
Place the coated eggplant onto the prepared baking sheet in a single layer. Bake for 10-15 minutes, or until golden brown and crispy on both sides.
Spread a layer of marinara sauce in the bottom of a large casserole dish. Layer some of the eggplant, some of the mozzarella slices, and some of the Parmesan. Repeat this layering process until all of the ingredients are used.
Bake for 20-25 minutes, or until the cheese is melted.