Ponzu (ポン酢, citrus-soy dipping sauce)

Ingredients

Equipment Needed

• •Fine-mesh strainer lined with a clean cloth
• •Small saucepan
• •Citrus reamer
• •Clean glass jar with a tight lid
• •Bonito shaver (kezuriki) if shaving whole katsuobushi, or freshly opened shaved flakes

Instructions

1. 1

   Juice the citrus

   Halve the citrus and juice it gently, stopping before the reamer scrapes hard into the white pith. The colored flesh gives aroma and acidity; the pith gives a dull bitterness that a week in the jar will not fix. Strain out the seeds and measure 1/2 cup.

   Yuzu and daidai belong to the colder months, while sudachi and kabosu come into their own from late summer into autumn. Let shun, the season when the fruit is at its prime, choose the citrus when you can.
2. 2

   Steep the konbu

   Wipe the konbu with a damp cloth, but don't wash it. That pale bloom on the surface is flavor, not dirt. Put the konbu in 1 cup cold water and warm it slowly over low heat, about ten minutes, until the water trembles and small bubbles climb the sides. Lift the konbu out before the water boils.

   You're steeping the kelp, not boiling it. Boil it and the dashi turns faintly bitter and slick, which is a poor start for a sauce that should taste clean.
3. 3

   Add the bonito

   Bring the konbu water just to a gentle boil, add the katsuobushi all at once, and take the pot off the heat. Leave it alone for two or three minutes, until the flakes sink. Strain through a cloth-lined sieve and let it drip by itself. Don't squeeze. Measure 1/2 cup dashi for the ponzu and let it cool.

   Squeezing presses out strong, oily flavors from the bonito flakes. The flakes have already given what you want; let the rest stay behind.
4. 4

   Quiet the mirin

   Put the mirin in a small saucepan and bring it just to a simmer for about thirty seconds, then take it off the heat and cool it. This softens the raw alcohol edge in a cold sauce. Don't boil it down into syrup; ponzu should stay lean and bright.

5. 5

   Mix the ponzu

   In a clean jar, combine the koikuchi shōyu, 1/2 cup cooled dashi, cooled mirin, and citrus juice. Taste it now. It should seem a little sharper and saltier than you want at the table, because resting will soften the edges. If your citrus is mild or you came up short, add unseasoned rice vinegar by the tablespoon.

   Keep the citrus juice raw. Heating it flattens the fragrance, and the whole point of ponzu is that cool lift against soy and dashi.
6. 6

   Rest the sauce

   Add the strip of citrus peel if using, making sure there is no white pith attached. Seal the jar and refrigerate for one week, shaking it gently once a day. Remove the peel after the first day so its aroma stays clean rather than bitter. Time does not make ponzu stronger; it makes the soy, acid, and dashi stop arguing.

7. 7

   Serve and store

   After a week, strain the ponzu again if it has any sediment, then pour it into small dipping cups. Add a few scallion rings only when serving, if they suit the dish beside it. Use ponzu with shabu-shabu, tataki, chilled tofu, grilled fish, or nabemono, the family of hot-pot dishes. Keep it refrigerated and use within one month.

Chef Tips

• •If Japanese sour citrus isn't available, bottled unsweetened yuzu juice is often better than tired fruit shipped past its dignity. A mix of fresh lemon and lime gives useful acidity, but call it a stand-in, not the same fragrance.
• •Use koikuchi shōyu here. Usukuchi is paler but saltier, and tamari is heavier; both can push the sauce away from the clean balance you want.
• •For a meatless table, make shōjin dashi: soak the konbu with one dried shiitake overnight, warm it gently, and strain. That is honmono for a temple table, not an apology, though it will not taste like bonito.
• •Don't reach for instant dashi when the stock is the backbone of the sauce. Ponzu has very few parts, so each one has to stand where you put it.
• •A week of rest is not fussiness. New ponzu is sharp at the elbows; rested ponzu meets the ingredient cleanly and then gets out of the way.

Advance Preparation

• •Make the ponzu seven to ten days before you need it. That rest is the main seasoning.
• •The dashi can be made one day ahead and kept refrigerated, but cool it fully before mixing so the citrus stays fresh.
• •Finished ponzu keeps about one month refrigerated. If the citrus aroma fades, brighten each serving cup with a few drops of fresh juice rather than adding more salt.

Frequently Asked Questions

Nutrition Information

1 serving (about 15g)