Wikipedia
Gyūdon
, literally beef bowl, is a Japanese dish consisting of a bowl of rice topped with beef and onion simmered in a mildly sweet sauce flavored with dashi ( fish and seaweed stock), soy sauce and mirin (sweet rice wine). It also often includes shirataki noodles, and is sometimes topped with a raw egg or a soft poached egg ( onsen tamago). A very popular food in Japan, it is commonly served with beni shōga (pickled ginger), shichimi (ground chili pepper), and a side dish of miso soup. Gyū is the prefix for anything cow-related, and don is short for donburi, the Japanese word for "bowl".