Ponzu Sauce is a simple Japanese sauce made from mirin, Bonito Tuna Flakes (aka “katsuobushi”), kombu (aka “konbu”, aka “seaweed”) and vinegar.
The ingredients are simmered briefly, then strained, then yuzu juice is added.
If you have time to make it the day ahead, then you can just mix everything, skip the simmering, and let the flavours marry until the next day. The simmering simply speeds up the blending of flavours.
If soy sauce is added, the sauce may be called “ponzu shouyu”, though added soy sauce is so common now that many people still just call it plain “ponzu” anyway.
Ponzu Sauce is used for sea foods, both for marinating them in, and basting them with while barbequing.
It is also used as a dipping sauce.
It is always served with Yosenabe and Shabu-shabu.
You can buy Ponzu Sauce already made in bottles. A well-known brand is “Ajipon”, available since 1964. Kikoman also makes Ponzu Sauce in North America.
(this takes into account that Yuzu fruit is all but unavailable outside Japan)
1 part soy sauce
½ part rice vinegar
1 part orange juice
2 – 3 cm (1 inch ) kombu kelp
Few pinches dried bonito
Mix all except orange juice, simmer for a few minutes, strain, add orange juice. Or mix ahead overnight, putting the juice in right at the start.
Bottled Ponzu Sauce can often be used interchangeably with soy sauce in recipes; it has the advantage, at least for brands like Kikoman’s, of being lower in sodium than even low-sodium soy sauce.
“Pon” = “citrus”; “zu” = “vinegary.”