Nagasaki's food is unlike anywhere else in Japan. Centuries of trade with China and the Netherlands produced fusion dishes that became local staples: champon (a noodle soup of Chinese origin invented here in 1899), sara udon (crispy noodles with thick sauce), Turkish rice (a single plate with pilaf, spaghetti, and tonkatsu), and chawanmushi served as a full meal rather than a side. Castella sponge cake, brought by Portuguese missionaries in the 16th century, is the city's signature sweet.