Salt Mackerel
Clean the fish by scraping off any rustylooking portions and the thin black membrane found on the inside, and lay it over night in plenty of cold water, with the skin side up. In the morning place the fish in a frying-pan on the fire, cover with fresh water, and slowly heat to the boiling point. Drain off this water, add just enough fresh water to cook the fish, and boil slowly until tender. Lift the mackerel out carefully (a pancake turner will be found most convenient for such work), and place it on the serving dish in the oven to keep hot while the gravy is being prepared. This is made as follows: drain off the water left in the frying-pan after the removal of the fish, until there is one-half pint remaining, then pour into the pan one pint of milk. When the liquid boils, add three tablespoons of flour stirred to a paste with two tablespoons of butter, and seasoned with salt and pepper. Let the gravy boil slowly three or four minutes stirring constantly until smooth; then pour it over the mackerel.
A plain salt-fish supper of the sort that appeared on breakfast and Friday tables well into the twentieth century. Everything hinges on the soaking and on keeping the poaching water below a rolling boil.
- Buy the right fishSalt mackerel is heavily dry-salted or brine-cured and sold split; look for it at Portuguese, Caribbean, Scandinavian and Asian grocers among others. Fresh mackerel is not a substitute here; it needs no soaking and will fall apart under this treatment.
- Skin side up, and mean itThe fish is laid skin up as the recipe directs; the usual explanation is that salt drawn out of the flesh sinks away from it rather than settling back in. Use a wide dish and plenty of cold water, and refrigerate overnight rather than leaving it on the counter.
- Taste before you cookCures vary enormously. After soaking, cut off a sliver and taste it raw or poach a scrap; if it is still fiercely salty, change the water and give it a few more hours. This is the one step that decides whether the dish is edible.
- The two watersThe first heating draws off the last of the salt and the strongest of the fishy liquor; it is discarded. The second water becomes the base of the gravy, which is why only half a pint of it is kept.
- "Boil slowly" means poachBring the second water barely to a shiver and hold it there rather than letting it roll. A split fish of ordinary thickness needs only a few minutes and is done when the flesh flakes at the thickest point; a true boil will shred the fish and toughen it.
- The frying-panUse a wide sauté pan or a shallow braiser that will hold the fish flat, with just enough fresh water to cook it as the recipe directs.
- The gravy proportionsHalf a pint of cooking liquid plus one pint of milk is three cups of liquid to three tablespoons of flour and two of butter, which gives a light pouring sauce rather than a thick one. Rub the flour and softened butter to a smooth paste first, then whisk it in bit by bit; adding it in one lump will leave you picking out flour knots.
- Season lastThe recipe seasons the flour-and-butter paste before it goes in, but the cooking water already carries residual salt into the gravy; taste and adjust after the sauce has had its three or four minutes.
- YieldA whole split mackerel of about a pound and a half, with this quantity of gravy, serves three or four with boiled potatoes.
Salt mackerel was one of the great cheap proteins of the North Atlantic. New England and Nova Scotian fleets took mackerel by the barrel through the nineteenth century, splitting, gutting and packing the fish in salt in graded barrels, and the resulting product travelled inland by rail to households that never saw the sea. Butterick's placing of it in the fish chapter reflects a kitchen where the salt barrel and the fishmonger were equally routine. The milk gravy is a common American treatment for salted fish — the same sauce goes over salt cod and finnan haddie — and its function is as much practical as pleasant, since dairy blunts whatever salt the overnight soak failed to draw out. Mackerel for breakfast is often said to have been a New England institution, and the timing of this recipe, with its overnight soak and morning cooking, quietly assumes that is when it will be eaten.