Preheat oven to 450°F; slice eggplants in ½ inch wide rounds and place on a baking sheet; sprinkle with salt and pepper on both sides and drizzle both sides generously with olive oil; bake 15-20 minutes per side flipping halfway through (30-40 minutes total) eggplant should be golden brown on both sides as if it was pan fried (this is important! make sure you get the eggplant nicely browned and tender.. may take slightly more or less time depending on your oven)
In a pan over medium heat, toast the breadcrumbs in olive oil with a pinch of salt until they are golden brown, stirring constantly; set aside
In a glass dish or Dutch oven, layer marinara, eggplant, Parmesan, basil, and breadcrumbs - repeat until all eggplant is used; top with mozzarella
Bake at 450°F uncovered for 30 minutes and then broil the top for ~2 mins until golden brown and bubbly - enjoy!
