Nitsuke Recipe (Japanese Simmered Fish)

Step 1

Gather all the ingredients.

Step 2

To start the kombu dashi, place ¾ cup water in a measuring cup and add 1 piece kombu (dried kelp). Allow it to steep to release flavor (this is cold brew kombu dashi). In the meantime, prepare the other ingredients.

Step 3

Place ½ lb cod fillet portions on a tray; I used my favorite stainless prep tray. Sprinkle ⅛ tsp Diamond Crystal kosher salt on both sides, including the skin, and let sit for 10–15 minutes. Nami's Tip: This step isn't for seasoning—just a light pinch of salt per fillet (about 4 oz or 113 g) is enough. Salting draws out excess moisture and helps remove fishy odor. Don't skip it! Too much salt can make the fish tough, so go light.

Step 4

Meanwhile, scrape the skin off 3 inches gobo (burdock root) with the back of a knife. Cut the gobo into thin slices lengthwise.

Step 5

Next, cut the slices in half crosswise. Soak in water for 5–10 minutes to remove bitterness and prevent discoloration. Change the water halfway. Drain and rinse.

Step 6

Peel 1 knob ginger and cut it into thin slices.

Step 7

After 10–15 minutes, you'll notice moisture on the surface of the fish. This liquid holds the fishy smell. Gently pat the fillets dry with paper towels.

Step 8

Boil just enough water in a medium saucepan to cover the fish. While waiting, prepare a medium bowl of cold water with several ice cubes. Once the water comes to a boil, turn off the heat. Gently add the fish and blanch for 15–20 seconds.

Step 9

Halfway through, gently flip over the fillets.

Step 10

As soon as the fish's surface turns white, remove it from the hot water. Place it in the ice water for about 10 seconds to cool and rinse off any residue. Then gently pat dry with clean paper towels. Discard the blanching water and quickly rinse the saucepan. Nami's Tip: This quick blanching step, called shimo-furi (霜降り), helps remove unwanted odors and surface proteins. Remember, you are not cooking the fish—just cleaning it for a better flavor and texture.

Step 11

Add the cold brew kombu dashi, hydrated kombu, and ¼ cup sake to the same saucepan. Gently place the fish fillets on top of the kombu, skin side up. Bring it to a gentle boil over medium heat. Nami's Tip: When you add sake and let it boil, the alcohol evaporates along with the fishy smell, leaving a mild, savory aroma behind.

Step 12

Add the burdock root. Once simmering, skim off the scum and foam from the liquid's surface with a fine-mesh skimmer for a clean, clear sauce. Nami's Tip: Burdock root helps to remove odors, so add it from the beginning.

Step 13

Remove the kombu; you can use it in other recipes like homemade furikake. Now, add the ginger slices.

Step 14

Add ¼ cup mirin and 1½ Tbsp sugar, stirring the broth carefully with chopsticks to dissolve the sugar (careful not to break the fish). Nami's Tip: What about soy sauce? When salty ingredients are added, the sweetness does not penetrate the ingredients as easily, so we'll add soy sauce later.

Step 15

Once simmering, reduce to medium-low heat. Place an otoshibuta (drop lid) directly on the fish and gently simmer for 10 minutes (Set the timer now). Nami's Tip: The drop lid holds the fish in place so it doesn't break apart and evenly distributes the seasoned broth all over for better flavor absorption. Find one on JOC Goods or learn how to make otoshibuta at home with aluminum foil.

Step 16

After halfway through (5 minutes in), lift the drop lid and add 3 Tbsp soy sauce. Gently shake the saucepan to mix and place the drop lid again.

Step 17

When the timer is up, remove the drop lid. Spoon the broth on the fish several times so the surface shines and the flavor infuses.

Step 18

Turn off the heat. Set aside and let cool slowly in the seasoned liquid. Keep the otoshibuta on so the fish doesn't dry out. When ready to serve, reheat gently until warm and serve the fish and gobo drizzled with seasoned broth on individual plates. Nami's Tip: I highly recommend cooling the fish for a few hours or even overnight in the fridge to soak up the delicious seasonings.

Step 19

Once completely cooled, transfer the leftovers to an airtight container and store in the refrigerator for up to 2–3 days or in the freezer for up to a month.