Preheat oven to 375 F.
Place eggplant, pepper, and onion in baking dish. Season with salt.
Mix olive oil, balsamic vinegar, and garlic. Pour over vegetables in baking dish. Add capers.
Bake at 375 F until eggplant is golden brown and tender, approx. 35 min.
Garnish with fresh basil and serve.