Heat olive oil in a large skillet over medium high heat. Roughly chop eggplant centers, and add to pan with onion, garlic, oregano, and pepper. Cook and stir until lightly browned. Spoon mixture back into eggplant, and sprinkle each with Parmesan cheese, bread crumbs, and parsley. Place in a shallow baking dish, and cover with tomato sauce and mozzarella cheese.
Bake in the preheated oven for 30 minutes, or until eggplant is fork-tender and cheese is bubbly. Serve immediately.