Tumminia (pictured at Molini del Ponte in Castelvetrano), also called Timilia, is an ancient grain variety cultivated in only a few locations in the Belice Valley in western Sicily. Once milled, it plays the role of principal ingredient in Castelvetrano’s Slow Food designated pane nero (black bread). Filippo Drago, owner of Molini del Ponte in Castelvetrano, makes…