Makes 6 sandwiches.
1. Combine zucchini, red peppers and 1/3 cup Italian dressing in plastic food-storage bag. Let stand 20 minutes.
2. Toast Italian bread. Grill or broil marinated vegetables 12 minutes, turning once.
3. Brush 6 slices toast with Italian dressing; top with vegetables and sliced mozzarella. Top with bread.