Grilled Vegetable and Mozzarella Panini

INGREDIENTS

• 1/2 teaspoon salt
• Vegetable oil cooking spray
• 1 cup shredded reduced-fat mozzarella
• 1 medium eggplant, cut lengthwise into 8 slices (1/4 inch each)
• 1 red bell pepper, cored, seeded and quartered
• 2 tablespoons balsamic vinegar
• 8 large fresh basil leaves
• 8 slices ciabatta
• 1 medium zucchini, cut into 8 slices (1/4 inch each)
• 1/8 teaspoon black pepper
• 1 tablespoon extra-virgin olive oil