Okay all of the other posts were correct except in the amount of usage
kombu gets in Japan.
To make Daishi which is the base of a lot if not most Japanese soups you
must use kombu. The kombu and dried cod are the only flavorings used to
make daishi. The cooking times are set by a lot of variables so it
takes practice to make it come out really good. That's why most people
here now buy instant daishi mix.
One other thing the Kombu is for flavoring. This IS NOT the type of
seaweed you would want to eat.
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