Dice the two eggplants into approximately one inch cubes. (Peeling the eggplant first is a personal preference; I don't.) Toss the eggplant cubes with 2-4 Tbsp of olive oil; add salt and pepper to taste. Spread into a single layer on a baking sheet and pop into preheated oven. Roast until eggplant is tender and beginning to brown, 15-20 minutes.
When eggplant is done roasting, pull out of the oven and top with crushed red pepper (if using), tomato sauce, parmesan, and mozzarella cheese. Place back in oven for approximately 10-15 minutes or until cheese is bubbling and starting to brown slightly. Serve with salad.