Kasu udon is an Osaka classic dish. When people hear the word Osaka, one might immediately think of takoyaki and okonomiyaki but never udon. However, udon is something really common in Osaka and most of the people here eat it nearly every single day. So why is it called "kasu udon"? We all know what udon means so I will not be covering that part but I will go into the meaning of "kasu". The Japanese word "kasu" means leftovers, however don't take this meaning the wrong way. This dish is a bowl of soup udon topped with spring onions and chopped up beef small intestine pieces. The small intestine pieces is sometimes fried before putting it into the udon. If you are up for a nice warm but cheap meal in Osaka then this is the food to go for.