A gingery, soy-tinted gravlax perfect for rice bowls and sushi.
Inspect your fish. Trim off any belly flap; pull out any remaining pin bones. Give it a quick rinse in cold water and pat dry with paper towels. Lay the fish, skin-side down, in a baking dish or other container to suit. In a small bowl, mix together the soy, mirin, and microplaned ginger, and pour slowly and evenly over the salmon, so as to keep as much as you can on the fish. Rub in gently to distribute.
Mix together the salt and sugar, and pour that evenly over the fish as well. Drape a layer of saran wrap over the salmon, then a layer of aluminum foil, to keep the saran wrap in place. Optionally weigh down the fish with a foil-wrapped brick or other relatively fish-sized, heavy object, like a large can or container of water, but don't stress. The salt will do 90% of the work for you.
Place your fish package in the fridge. After at least 6 and up to 12 hours, drain out the liquid that has accumulated in the dish. All this means is taking off the weight, lifting up a corner of the wraps, and holding the fish back through the foil while you tilt the pan into the sink. Sorry if this is insultingly obvious, but I have some crazy stories. Anyway, don't let the fish sit around in that super-salty juice or it will start to reabsorb. Drain it at least once after 12 hours, once after 24, and once a day thereafter.
Let's imagine your fish has now been curing for a full 24 hours. You've probably drained out about 5% of its weight in water, and that's probably about enough for most uses. This particular recipe is mainly for sushi or salmon bowls, where it's good to be a little juicy. But we're in personal preference world, and you could let it go another day or two, or even hold it in the fridge up to a week.
But at last you are ready. Finish off your fish by giving it a quick, minimalist rinse in cold water to get rid of the sugar and salt, and pat dry once again. Drizzle and gently distribute an extra teaspoon of soy over the salmon, place on a rack, and leave uncovered in the fridge overnight, or for another 12 hours. It will develop a nice bit of gloss. Wrap the fish up in plastic wrap and foil; it will last at least another week in the fridge.
Short of time but still want the nice gloss? Anoint with soy and put the fish under an ordinary room fan for an hour. Have an interesting liquor pantry? Drizzle on a bit of sake or ginger liqueur before the final soy wash.
This cure has a definite oriental feel and, to my mind, is weird on a bagel with cream cheese. It is great cut into small cubes for a rice bowl, as below, or made into strips for a salmon roll. But it IS lovely in thin slices, eaten right out of hand. Mmm, I think next time I do this I will lay out some very thin slices on a nice plate, tiradito-style, and drizzle with a bit of soy sauce mixed with fresh lime juice and mirin.