Slice the eggplants into ½” thick disks. Season the slices with salt and set aside on rack to “drain” for 30 minutes. Wipe the salt and excess moisture off with paper towel.
Preheat the oven to 250 degrees F.
Place the flour in a dredging bowl. Place the panko, oregano, and garlic powder in another dredging bowl, and stir to combine. In a third bowl, whisk together the eggs with a pinch of salt, pepper, and a tablespoon of water.
Dredge the eggplant slices in the flour, shake off the excess, then in the egg, shake off the excess, then into the panko bread crumbs. Set aside.
Heat up a skillet over medium heat, and fill with enough olive oil to coat the bottom of the pan about ¼” up. Place a single layer of eggplant slices into the skillet and fry for about 5 minutes on each side, until golden brown. Make sure to watch that the eggplant slices aren’t burning, and adjust the heat up or down as needed.
Place the fried eggplant slices on a tray, season with salt and pepper, then keep in the warm oven while you finish frying all batches of eggplant. Add more olive oil to the skillet as needed.
When you’re done frying all the eggplant, remove the eggplant from the oven and increase the temperature to 350 degrees F.
To assemble each sandwich, split the hoagie roll in half, then put on a single layer of eggplant slices. Season with a pinch of salt and pepper, then add a couple spoonfuls of grated parmesan, then a couple spoonfuls of marinara sauce, then a single layer of sliced mozzarella. Drizzle with olive oil, then put the top of the sandwich on and bake for 10 minutes until the cheese is melty. Tuck a few basil leaves into each sandwich, then enjoy!
Recipe adapted from: fifteenspatulas.com.