Sicilian Zucchini Pizza

Name: Sicilian Zucchini Pizza
Ingredients: 1/2 red onion, peeled and cut into 4 wedges; 2 Tbs. olive oil, plus more for drizzling; Salt and freshly ground pepper, to taste; 4 zucchini, cut lengthwise into slices 1/4 inch thick; 1/2 batch Sicilian-Style Pizza Dough; Cornmeal for dusting; 1 cup tomato sauce; 2 cups grated provolone cheese; 1 cup grape tomatoes, halved; Grated Parmigiano-Reggiano cheese for sprinkling; 2 Tbs. thinly sliced fresh basil