The tart, faintly purple tang doesn't come from vinegar or extra lemon — it's sumac, a ground dried berry, dusted over the top right before serving.
Chopped cucumber, tomato, radish, and romaine are tossed with torn bread fried or toasted until crisp, dressed in olive oil, lemon, and pomegranate molasses, and finished with a heavy dusting of sumac. Beirut's produce markets and mezze restaurants keep it on the table as a way to use up the last of the week's bread.