Dashi
Other kinds of dashi stock are made by soaking (or putting) kelp, shiitake, or niboshi in cool water for many hours. Or they are made by heating them in water nearly to boiling and then straining the resulting broth. Kelp stock or konbu dashi is made by soaking kelp, or sea tangle, in water. Shiitake dashi stock is made by soaking dried shiitake mushrooms in water. Niboshi dashi stock is made by soaking dried small sardines. Some use niboshi after taking off (or pinching off) their heads and entrails in water, but others use whole niboshi as this way get tasty dashi, too.