Kaburazushi (Koji-Fermented Turnip and Yellowtail)

Buy the salt-cured yellowtail and turnips refrigerated from an authorized seller and check their use-by dates.

Do not use swollen packages or products with an uncertain cold chain.

Cook 360g rinsed rice and cool it to about 60C.

In a sanitized vessel, mix the rice with 200g rice koji and 400ml boiling water. Hold near 50C for 8 hours to make sweet koji, then cool promptly.

Dry the cured turnips thoroughly and cut a pocket into each thick round without cutting through.

Rinse the cured yellowtail briefly in cold water, dry it, and slice to fit the turnip pockets.

Insert one yellowtail slice into each turnip pocket.

Cut 100g carrot into thin flower shapes, seed and slice 2 chilies, and julienne 15g yuzu peel after removing the white pith.

Spread a thin layer of sweet koji in a sanitized, fully dried food-safe vessel and pack the filled turnips tightly.

Cover each with generous sweet koji, scatter carrot, chili, and yuzu, and repeat the layers.

Cover the top with 200g cured turnip leaves and add a clean drop lid and weight.

Mature for 7 to 10 days under refrigeration at or below 4C, checking the vessel and aroma daily.

When the koji smells clean and tangy and the layers are seasoned, remove portions with clean tongs and slice.

If there is putrid odor, mold, abnormal gas, or slime, do not taste it; discard the entire batch.