How to Make It
Heat the oven to 450°. Put the eggplant cubes on a large baking sheet and toss with 2 tablespoons of the oil and 1/4 teaspoon each of the salt and pepper. Arrange the cubes in a single layer and roast, stirring occasionally, until soft and golden, about 15 minutes. Set aside to cool.
Reduce the heat to 350°. Wrap the pitas in aluminum foil, making two packets of four, and warm in the oven for 10 minutes.
Meanwhile, put the roasted eggplant, the lemon juice, tahini, cumin, garlic, and 1/4 teaspoon of the salt in a blender or food processor puree until smooth.
In a medium glass or stainless-steel bowl, combine the lettuce, tomato, and cucumber. Add the vinegar and the remaining tablespoon of oil and 1/4 teaspoon each of salt and pepper. Toss to combine. Spread some of the baba ghanouj on each pita and then top with the salad.