Mame Kazunoko (Green Soybeans and Herring Roe in Dashi)

Sort 300g dried Aobata soybeans, discard damaged beans, and rinse.

Cover with 1000ml water in a large pot and soak 10 to 12 hours in the refrigerator at 4C or below.

Bring beans and soaking water to a boil and skim.

Simmer 20 to 30 minutes; split one, and when no raw aroma or white chalky center remains, drain and cool completely.

Submerge salted roe in 1000ml cold water and refrigerate.

Change with fresh cold water every 8 hours for 24 to 48 hours; taste a small cut and remove when no longer excessively salty.

Peel the thin membrane from the roe with fingers and rinse once in clean cold water.

Blot dry, cut to bite-size 2cm pieces, and hold at 4C or below.

Mix 200ml bonito dashi with 2 tablespoons mentsuyu.

Taste and use up to 1/4 teaspoon salt only if needed. Put cooled beans and roe in a covered container and pour in seasoning.

Fold twice from bottom to top without breaking roe and marinate 2 hours at 4C or below.

Drain a little liquid with a clean spoon and serve beans and roe evenly chilled.