In Japan, castella cake has been popular for generations. It's the descendant of "pao-de-lo," a dessert brought to 16th-century Japan by Portuguese merchants. Also from Portugal is Paulo Duarte, a confectioner in Kyoto Prefecture who made it his mission to reintroduce Japan to "pao-de-lo." We follow his attempt at baking the "missing link" between the 2 cakes. Don't have a sweet tooth? Then tag along as we later visit the Tokyo shop of Vietnamese-born Tran Van Trung for some of his famous fish-stock ramen.