1. Heat a grill pan over medium-high heat; coat pan with cooking spray. Coat eggplant slices with cooking spray, and place in pan. Cook 4 to 5 minutes on each side or until tender.
2. Combine eggplant and next 4 ingredients in bowl, tossing to coat.
3. Slice ciabatta loaf in half lengthwise, cutting to, but not through, other side.
4. Arrange vegetable mixture evenly over bottom half of bread; top with cheese and top half of bread. Cut into 4 equal servings.
5. Place sandwiches in grill pan over medium-high heat. Place a piece of foil over sandwiches; top with a heavy skillet to press sandwiches. Cook 2 minutes. Turn sandwiches; replace foil and heavy skillet. Cook 2 minutes or until golden brown and cheese is melted. Serve immediately.