Dashi is an essential in the Japanese kitchen. It is used like chicken broth or other stocks, as a flavored liquid for simmering vegetables or as a base for soups. It should be used immediately after you make it, since the flavorings are at their best then. Each of the following methods of making dashi is quick and easy and produces four cups of broth, with a distinctive color and flavor. Take your pick. (Note: You can also make “instant dashi” by starting with Instant Dashi Powder, available at Japanese and Korean groceries.) Use as directed in individual recipes.