Gyudon can count as a representative of Japanese fast food culture. On the street of Tokyo, Yoshinoya, Matsuya, etc... There must one of them nearby. Comrades of dieter always think that this beef rice is consider a low fat dish, but they forgot most of them they choose fatty beef. If you want to homemade a low fat gyudon, remember to use the lean beef, cut into thin slice. So this help penetrate the onion flavor to the beef, and make the authentic Japanese gyudon.