Start to finish: 30 minutes
⅓ cup white vinegar
¾ teaspoon white sugar
Kosher salt and ground black pepper
1 small ripe tomato, cored and chopped
1/2 small red onion, thinly sliced
1 1/2 pounds eggplant, cut into twelve 1/2-inch-thick rounds
3 tablespoons extra-virgin olive oil
4 teaspoons za’atar
¼ cup tahini
2 tablespoons lemon juice
2 to 3 tablespoons harissa paste
Two 8-inch pita rounds, each cut into half-rounds
Heat the broiler with a rack about 6 inches from the element. Line a rimmed baking sheet with foil and mist with cooking spray. In a small bowl, stir together the vinegar, sugar and ¼ teaspoon salt until the sugar and salt dissolve. Stir in the tomato and onion; set aside while you prepare the eggplant.
Brush both sides of the eggplant slices with the oil, then sprinkle with the za’atar, along with salt and pepper. Lay the slices on the prepared baking sheet and broil until well charred and a skewer inserted through the center meets no resistance, about 12 minutes, flipping the slices halfway through.
Meanwhile, in another small bowl, whisk together the tahini, lemon juice, and ¼ teaspoon each salt and pepper. Whisk in the harissa and 3 tablespoons water; set aside.
When the eggplant is done, set the baking sheet on a wire rack. To fill each sandwich, open a pita half and spread 2 to 3 tablespoons tahini sauce inside. Place 3 eggplant slices in the pita, followed by a quarter of the onion-tomato mixture.