- Thinly slice squash, zucchini and bell peppers. Cut onion into thin wedges and garlic into quarters.
- Toss together vegetables, garlic, 2 Tbsp. soy sauce and black pepper; place mixture in oiled grilling basket.
- Cook vegetables in covered grill over medium-hot coals 15 to 20 minutes, or until tender, opening lid and stirring once or twice.
- Transfer vegetables to large bowl and toss with 1 Tbsp. soy sauce.
- Brush bread shells with remaining 1 Tbsp. soy sauce.
- Top shells with half of Parmesan cheese, then with equal amounts of vegetables and mozzarella cheese. Sprinkle with remaining Parmesan.
- Bake on cookie sheets in 450º F. oven 8 minutes, or until cheese melts and vegetables in center of pizzas are hot.