I spent a week in Warsaw and ate more pierogi than I could shake a stick at. These beloved traditional Polish dumplings come filled with potatoes, cheese, meat, mushrooms and even fruit. Boiled or fried, they may look familiar to anyone acquainted with jiaozi, the Chinese dumpling, although their flavours are distinctly Polish. This is not to suggest that dumplings travelled directly from China to Poland. One theory posits that dumpling-like foods – from Nepalese momo and Central Asian and...