It was Sunday morning at the farm that Mara and Maurizio Martin, of Venice’s Da Fiore Restaurant, own on the mainland. We were going to have a barbecue, and as Maurizio was collecting the wood for the fire, Mara asked whether I’d like some pickled zucchini with the meat. “Sure,” I said. “When did you make them?” “I haven’t yet,” she replied. Starting from scratch, she was, to my surprise, putting