Grilled Pizza with Hummus and Rosemary Summer Squash

Name: Grilled Pizza with Hummus and Rosemary Summer Squash
Ingredients: 2 small zucchini, sliced on the diagonal 1⁄4 inch (6 mm) thick; 2 small yellow squash, sliced on the diagonal 1⁄4 inch (6 mm) thick; 1 Tbs. finely chopped fresh rosemary; 2 Tbs. olive oil, plus more for grilling; 1 tsp. red wine vinegar; Salt and freshly ground pepper, to taste; 1 lb. (500 g) purchased whole-wheat pizza dough; All-purpose flour, for dusting; 1 cup (10 oz./315 g) prepared hummus; Chopped fresh flat-leaf parsley for garnish (optional)