"Shumai (焼売) is a type of Chinese dim sum (a light meal) consisting of minced pork, shrimp, or crab mixed with chopped scallions and garlic, wrapped in a square-shaped dough made of wheat flour and steamed. It is a characteristic of shumai that the top part is not entirely covered so that the filling is visible. It is also known as siu mai or shaomai.


In Japan, there is a shumai bento (シウマイ弁当, shumai lunch box) sold by Kiyo-ken (崎陽軒), which is the most popular ekiben (railway boxed lunch) in Japan. Without this ekiben, the popularity of shumai in Japan may not have been as high as it is today. Kiyo-ken started as a small shop selling simple food and drinks at a Yokohama station. As ekiben did not sell well in Yokohama due to its proximity to Tokyo, the first owner of Kiyo-ken, Mr. Nunami Mokichi (野並茂吉), thought he needed to create a local speciality food to sell ekiben in Yokohama. Mr. Nunami searched for local speciality food in Yokohama's Chinatown (the largest Chinatown in Japan). He focused on shumai, which is served as an essential side dish at Chinese restaurants. He scouted shumai chefs and developed the shumai bento, which he sold as siu mai bento in 1928. Siu mai bento, which is bite-sized and delicious even when cold, quickly became popular and helped spread shumai's popularity throughout Japan."