Choose your fish. The same rules Becky Krystal laid out in her ceviche guide apply here: make sure the fish is fresh, ask where it’s from, and so on. Farm-raised is a good choice, says Goodman, because the purveyor can guarantee it’s free of parasites. Buy from someone you trust and bring a few ice packs to keep that fish extremely cold until you start curing — ideally within a day of purchasing.
A fun way to dive into curing is to purchase six- to eight-ounce portions of a fillet, so that you can play around with seasonings without having to commit. You can cure with skin on or off — skin on slows the cure’s absorption and gives you something to hold on to while slicing.
As for the type of fish, Oakland, Calif.-based cookbook author Nik Sharma prefers ones with a little more oil, such as salmon. The coriander gravlax from his book, “Season: Big Flavors, Beautiful Food” (Chronicle Books, 2018), is flavored with Darjeeling tea leaves and black peppercorns. London-based cookbook author Alissa Timoshkina suggests anything meaty, dense and firm — she has cured mackerel, cod and other fish local to Siberia, where she’s from. Her book, “Salt & Time: Recipes from a Russian Kitchen” (out now from Mitchell Beazley in the U.K. and on Aug. 25 in the States), includes a recipe for cured whole mackerel. In addition to those recipes, I had great results with a piece of Loch Etive trout. Ask your fishmonger what they would recommend for curing and you may just be surprised by a new-to-you variety.
Pick a few flavorings. “The most basic is salt and sugar,” says Timoshkina. “But you can improvise and add a bit of chile, garlic, different herbs.” In her recipe, she stuffs the cleaned whole mackerel with dill, parsley and/or purple basil for “an aromatic quality.”
Sharma uses ingredients with a strong aroma and taste. “Even though you’re infusing flavor, it’s mostly at the surface level,” he says. “If you use a weak spice you don’t get much impact.” For an extra pop of color, he also suggests adding beet, cherry or blueberry juices. For less mess, use fresh fruit and vegetables — per his suggestion, I grated about a tablespoon of raw beet, then packed it on top of the salt and sugar layer. I was rewarded with a vividly dyed hunk — the beet flavor came through nicely, too.
Alcohol is another way to add and enhance taste, as, Sharma explains, it “helps draw out some flavor … that water cannot.” Consider gin, aquavit, whiskey or anise-flavored spirits, for starters. Just a tablespoon or two will do; brush it directly onto the flesh before the curing mixture, or sprinkle on top. Sharma’s done it both ways and noticed no difference between them.
Use a coarse salt, such as kosher, then add other flavors at will. For example:
Grated raw beet + aquavit + grated lemon zest + white sugar
Bourbon + fresh thyme + fresh tarragon + raw sugar
Fennel fronds + crushed coriander seed + grated orange zest + dried chile flakes + white sugar
Other flavors to consider: tea leaves, such as the smoky Lapsang souchong; dried hibiscus flowers; various crushed peppercorns; that random spice blend somebody gave you; whichever highly aromatic and abundant herb you’re growing. Get wild! Be funky!
Start curing and practice patience. Once you’ve gathered your flavorings, get out your digital scale and calculator. The amount of salt should be about one-fifth the weight of the fish. A one-pound piece of fish will need about 3.2 ounces of salt; 6 ounces of fish — 1.2 ounces of salt, and so on. While it may seem like a lot of salt, remember: you are not personally absorbing all of that sodium, and neither is the fish: you’ll scrape or rinse off the cure before eating.
Some recipes call for equal amounts of salt and sugar, others for half the sugar. While you should be somewhat strict about the amount of salt, since it draws out moisture and thus preserves the fish, you can play more fast and loose with the other flavorings.
Tear or bruise fresh herbs to release their aroma. Likewise, grind or pulverize seeds, dried flowers, peppercorns and other spices. Mix the salt, sugar and flavors of choice in a small bowl and lay your fish on a piece of parchment paper. Rub the mixture over every surface of the fish — and inside if curing whole. (If you’re doing the latter, ask the fishmonger to gut and clean the fish first, or you’ll have to!)
Top with freshly grated beet and sprigs of herbs, if using. Then, wrap the fish in parchment, lay it flat it in a dish (to prevent leakage), put a few heavy cans on top and transfer to the refrigerator. (For whole fish, Timoshkina’s recipe says to simply tie the herb-topped fish with string — no weight necessary.) Turn the fish over about once every eight hours.
The curing time depends on the size of fish and the finished texture you desire. The fish will visibly shrink as it releases liquid, resulting in a firmer texture and glossy flesh. For larger portions, somewhere between 24 and 48 hours is ideal. (I let small portions go for 24 hours once and wished I had checked them slightly sooner.) Sharma suggests slicing off a thin piece to decide if you like the taste and texture; if not, keep it going.
When it’s ready, discard any large herbs, then scrape or rinse off the cure, and pat the fish dry. Thinly slice the fish at an angle (against the grain) with a sharp knife. For easier slicing, you can even freeze your fish for an hour or two, as in this recipe for Ouzo and Lemon Cured Salmon. If you cured a whole fish, cut it across into about 1-inch chunks — through the skin, spine and all — and discard the head and tail. Pull the skin off with your hands and/or teeth and eat around the bones. “It’s a very messy affair,” writes Timoshkina.
Eat your cured fish within a week, or freeze it for up to three months. (Timoshkina does not recommend freezing the mackerel.)
Make your presentation pretty by laying the fish over plenty of fresh greenery. Serve with crackers, bagels or thin slices of dark, sturdy bread. A selection of piquant mustards and cured/pickled things — capers, olives, peppers, onions — help to cut through the fish’s richness. Just about everyone appreciates lemon and lime wedges. Cream cheese, thick yogurt or a horseradish-spiked sour cream are never a bad idea. To drink, choose something bright and slightly effervescent. Or make like the Russians: Pair your cured fish with a cold beer and toast to the golden hours of summer.