Summer Panzanella

Name: Summer Panzanella
Prep time: 15 min
Total time: 15 min
Cuisine: American, Italian
Ingredients: 1/4 c. extra-virgin olive oil, plus more for brushing; 2 3/4"-thick slices country bread; 1 medium zucchini or summer squash, halved; 1/2 large red onion, cut into 4 wedges; Kosher salt; Freshly ground black pepper; 1 clove garlic, minced; 2 tbsp. red wine vinegar; 4 c. diced mixed tomatoes (such as heirloom, vine-ripened, cherry, and grape); 1 c. cubed fresh mozzarella; 1/2 c. packed fresh basil leaves, torn into bite-size pieces; Balsamic glaze, for drizzling