A kind of caged steamed snacks made of noodles and stuffed with fillings. It originated later than baozi and appeared in Metropolitan City (now Beijing) in the Yuan Dynasty. Its shape is folded like a flower, and the skin is thin and the filling is tender. Later, it was also written as "siu mai", "siu mai", "a little plum", "siu mei", etc. In the 14th century, the Korean "Park Tongsi", a book on the history of Korea, wrote that "siu mai" is a kind of steamed snack with the filling. In the 14th century, Korea's Park Tongsi: "Soy Sour Stuffed Siu Mai", note: "Siu Mai is made of thin slices of wheat flour, wrapped in meat, steamed, and eaten with soup, and is called Siu Mai in the dialect. ...... The noodles are used as the skin, the meat as the filling, and the top is used as the stamen of the flower." The Qing Ping Shan Tang Talking Book. Fast-talking Li Cuilian's Records": "What is so difficult about siu mai and plaque food, I can do it in three soups and two cuts." Plaque food, dumplings. Jiading County Record: "[Yarn hats] are made of flour, with thin sides and thick bottoms, stuffed with meat, and are best eaten when steamed. Because the shape is like a hat, so the name." According to "yarn hat" is "slightly sold" the black reading. The Tenth Episode of The History of the Confucian Forests: "There were two plates of dim sum on the table - a plate of siu mai with a heart of pork, and a plate of dumplings steamed with goose oil and white sugar." Fu Chongru (Chengdu General View. Chengdu's Food Categories and Recipes": "Various kinds of siu mai, big meat siu mai, ground vegetable siu mai, frozen vegetable siu mai, mutton siu mai, chicken skin siu mai, pheasant siu mai, golden hook siu mai, veggie gravy siu mai, sesame siu mai, plum blossom siu mai, and lotus seed siu mai."