Directions

1. Make hummus vinaigrette: In a small bowl, whisk together hummus, vinegar, 1/4 cup olive oil, and the oregano. Add 1 to 2 tsp. water to reach a good drizzling consistency. Season with 1/4 tsp. each salt and pepper, and set aside.
2. Preheat a grill to medium-high heat (400°-450°F).
3. Cut tomatoes into wedges and set aside (you won’t be grilling them). Cut halloumi into 1/4-inch-thick slices. Cut zucchini into long 1/4-inch planks. Peel onion and slice into rings about 1/4 inch thick. Brush flatbreads and halloumi with olive oil, using about 2 Tbsp. Put zucchini and red onion in a large bowl, toss with the remaining 1 Tbsp. olive oil, and sprinkle with the remaining 1/4 tsp. each salt and pepper.
4. Oil the grill grate using tongs and a wad of oiled paper towels (and oil the grate again before grilling halloumi). Grill vegetables, flatbread, and cheese, in batches, with the lid closed: Grill zucchini and red onion, turning once, until tender and grill marks appear, 2-3 minutes per side. Transfer to a sheet pan. Grill flatbread and halloumi, turning once, until grill marks appear, 1-2 minutes per side. Transfer to the sheet pan.
5. Arrange grilled vegetables and halloumi on flatbreads. Top with olives, tomatoes, and arugula. Drizzle flatbreads with hummus vinaigrette, and cut into pieces before serving.