Today Yoshinoya is one of Japan's largest fast food chains .
It also has restaurants in Hong Kong, China, Malaysia, Singapore, Thailand, Taiwan, United States, Philippines and Indonesia.
Yoshinoya's core menu items are gyudon (beef bowl), butadon (pork bowl) and gyunabedon (beef, tofu, and vegetable bowl). They also offer seasonal dishes such as unadon (eel bowl).
From 2003-2005 Japan banned imports of American beef (because of mad cow disease in US beef). This was a crisis for Yoshinoya — at the time beef bowl was it's main product.
Rather than look for a new supplier Yoshinoya discontinued beef bowl altogether. At the time, Japanese costumers were fearful of mad cow disease. Yoshinoya introduced new products. Pork bowl became their main offering.
The substitution was successful. So successful that they were reluctant to put beef bowl back on their menu — fearing a repeat of the mad cow incident. Finally, in 2006 they brought beef bowl back for one day only. Lines formed at Yoshinoya restaurants across Japan.
Eventually, they brought beef bowl back as a permanent menu item. It's only available during limited hours (most Yoshinoya are 24/7).
Yoshinoya is trying to diversify its menu to attract more female customers. Currently, most Yoshinoya customers are working age men who want quick cheap food.
Yoshinoya is a recommended experience for tourists to Japan. It's cheap (as little as 270 yen ~ $3 US for a beef bowl) and tasty. The restaurants have a interesting atmosphere.