Dashi Kombu (dried kelps) is used extensively in Japanese cuisines as one of the three main ingredients needed to make dashi, a soup stock. Kombu is usually sold dried or in a dried shred called "Oboro kombu". It may also be eaten fresh as sashimi. Making kombu dashi is simple though kombu dashi powder may also be used. A strip of dried kombu in cold water is brought to a boil as the very first step of making dashi and the softened kombu is commonly eaten after cooking. It can also be sliced and used to make tsukudani, a dish that is simmered in soy sauce and mirin. And do not forget to used this dashi kombu when you make shabu shabu dish at home.
Kombu may be pickled with sweet and sour flavoring and are cut into small strips 5 or 6 centimeters long and 2 centimeters wide. These are often eaten as a snack with green tea.
It is often included when cooking beans, putatively to add nutrients and improve their digestibility.