Kelp Mushroom Relish

What to do with Kelp?  Has this question been bothering you too?  If the answer is no, you probably haven't yet made dashi -- the sea stock that is the foundation of many Japanese dishes.  First of all, what is kelp (or kombu in Japanese)?  It is a sturdy seaweed used to make stock.  After 5 years of throwing it in the trash I finally have a solution to this persistent problem -- Kelp and Mushroom relish.    This is another wonderful idea I got out of Washoku cookbook by Elizabeth Andoh.

The recipe calls for enoki mushrooms.  I was able to find them at Miso market in Cambridge, but wouldn't be surprised if Russo's in Watertown carries them too.  This was my first time working with enoki.  If Alberto Giacometti made a sculpture of a mushroom, it would look like enoki -- exceptitonally tall and thin.  But if you don't have enoki on hand, try shiitake mushrooms, sliced paper thin.

The resulting relish is an umami bomb.  It has a fabulous balance between saltiness and sweetness with a pleasant little tang from the vinegar.  We ate it warm over rice and stuffed chilled leftovers into onigiri (rice balls that are the Japanese equivalent to a European sandwich).

A note about ingredients:

If you don't make dashi often, and don't have enough kelp, you can cut the recipe in half, or simply pour boiling water over kombu and let it sit for a few minutes.  Buy real sake in a wine store, not "sake for cooking."

My notes are in [square brackets].

Kelp and Mushroom Relish

from Washoku: Recipes from a Japanese Home Kitchen by Elizabeth Andoh

pages 110-111

© Elizabeth Andoh

Makes about 1/2 cup

Several pieces kombu, about 50 square inches total, left over from making stock

2 cups cold water

3 tablespoons rice vinegar

1 teaspoon sugar

1 teaspoon sake

3 tablespoons mirin

4-5 tablespoons soy sauce

1 package enoki mushrooms, about 3 ounces, trimmed and cut into 2- to 3-inch lengths

1. Slice the kombu into narrow strips 1.5 inches long [I made my strips 1/16 inch wide].  In a nonreactive saucepan, bring the water to a rolling boil over high heat and add the vinegar.  The vinegar helps tenderize the kombu and eliminate any questionable bacteria if you are recycling the kombu from a previous use.  
2. Reduce the heat to maintain a steady, though not vigorous boil and cook the kombu for 4 to 6 minutes.  The water may become murky and develop a green cast.  This is normal.  Test for doneness: pinch a strip or two; they should yield easily.  If they do not, continue cooking for another 2 to 3 minutes.  Drain, rinse in cold water, and drain again. 
3. Rinse and dry the saucepan and add the sugar, sake, mirin, and soy sauce.  Place over low heat, bring to a simmer, and add the drained kombu.  Simmer for 2 to 3 minutes, and then add the mushrooms.  Cook over fairly low heat for about 3 minutes, stirring frequently.  The liquid will become very foamy as it reduces rapidly; be careful not to let it scorch.
4. When the kombu looks glazed and the liquid is nearly gone, remove the pan from the heat and let the contents cool to room temperature naturally.  Serve immediately.
5. Transfer any leftovers to a glass jar, cover the top with plastic wrap, and then screw the lid in place.  Store the relish in the refrigerator for up to 2 weeks.  Each time you take some relish from the jar, reseal it with fresh plastic wrap before replacing the lid.