Ash-e haft daneh, the soup of seven seeds, is cooked as nazri, a votive offering, on Tasua and Ashura in Muharram, when families in Tehran, Kashan and Yazd stir huge cauldrons in the street and share bowls with neighbours and passers-by. Wheat, barley, rice, chickpeas, beans, lentils and mung beans cook slowly into a thick, nutty soup with herbs, topped with fried onion and mint. Serve it in bowls with bread. The mistake is adding all the grains together; they cook at different speeds, so the hard ones go in first. Chef's tip: soak everything except the rice and lentils overnight, each in its own bowl, and you'll cut the cooking time by an hour.