Chef Yotam Ottolenghi's culinary journey takes him to Istanbul, where he tastes fish from the waters of the Bosphorus, shops for vegetables and samples the street food. Inspired by what he sees, he prepares Turkish pizza topped with spicy beef, pine nuts and a crunchy salad by baking it in a traditional stone oven, before cooking a casserole bursting with prawns, squid, tomatoes and cheese. He also visits a factory to help make baklava, one of the country's most popular desserts