Select eggplant that has a smooth peel with no blemishes or soft spots. A small young eggplant has a tender peel that doesn't require removal.
To reduce the fat in each serving of these sandwiches by about 9 grams, use reduced-fat mozzarella cheese and omit the olive oil. Instead, spritz the vegetables with olive oil-flavor or regular nonstick cooking spray.
Toast the bread on the grill, watching it carefully and turning once, until it is light golden brown.
These sandwiches make nice melts. Arrange them on a sheet of heavy-duty foil and place it on the grill. Close the grill and heat it just until the cheese is melted.