PREPARATION:
- Remove and discard mushroom stems; set aside. (Mushroom caps may be thinly sliced, if desired.)
- Spray 6 (16-inch-long) sheets of foil with nonstick cooking spray. In center of each sheet, layer onion slices, bok choy, corn, bell pepper and mushrooms.
- Combine water, rice wine, soy sauce, oil, ginger and salt in small bowl. Drizzle over vegetables in each packet.
- Seal packets by bringing two long sides of foil together over vegetables; fold down in series of locked folds, allowing for heat circulation and expansion. Fold short ends up and over again. Press folds firmly to seal packets. Turn packets over several times to coat vegetables completely.
- Grill packets on covered grill over medium to low coals about 10 minutes, turning every 2 to 3 minutes. (Vegetables will continue to cook once removed from heat.) To serve, carefully open one end of each packet and slide vegetables onto plates.
