As far as condiments and flavourings go, I love miso. I use it rather unconventionally in salad dressings and also in sauces/ marinades. The savouriness of miso lends well to eggplant. You could use the same technique with zucchini (cut it lengthways).
2 eggplants, cut into 2cm thick slices
2 -3 tablespoons of vegetable oil (like sunflower)
100g mozzarella, grated