Soy-Ginger Fried Mackerel (鯖の竜田揚げ, Saba no Tatsuta-age)

Mackerel frightens people a little. It has a strong character, and when it is tired it tells you so with no manners at all. That is useful, really. Choose saba that is glistening fresh, cook it the day you buy it, and this dish becomes straightforward: marinate, starch, fry.

Tatsuta-age is not a heavy batter. The fish is seasoned first with soy, sake, and ginger, then dusted in potato starch so the surface fries into a fine, dry crust. The starch does two jobs. It keeps the marinade close to the fish, and it seals the outside quickly so the flesh stays juicy. Flour gives a softer coat. Potato starch gives the clean bristle we want here.

The one detail that decides it is dryness before frying. Let the marinade do its work, then wipe off the excess and dredge just before the fish meets the oil. Too much wet marinade darkens before the fish is cooked, and too much loose starch clouds the oil. Nothing hidden, nothing muddy. This is weeknight washoku with teeth: a bowl of rice, something green, perhaps a sharp grated daikon beside it, and the method doing honest work.