Wikipedia
is a type of Japanese omelette, which is made by rolling together several layers of cooked egg. These usually are prepared in a rectangular omelette pan called a makiyakinabe.
There are several types of tamago. Tamago is made by combining eggs, and sometimes sugar or soy sauce. Additionally, sake is used in some recipes. An alternative version includes a mix of shrimp puree, grated mountain yam, sake and egg, turned into a custard-like cake.
Tamago is served around the world in the form of nigiri, and also appears in many types of sushi rolls. In Japan, it is also served as a breakfast dish and in other preparations. As part of a sushi/sashimi dinner tamago is usually taken as the final course, in essence a dessert bite. In many sushi circles, the strength of a kitchen is determined by the quality of their tamago.