From Cook's Illustrated:
Miso-glazed salmon promises firm, flavorful fish with a glazed, lacquer-like exterior but takes 3 days to prepare. We wanted to make a dish that pulled back on the traditional approach (and shortened the process) but still achieved the depth of sweet-savory flavor that this dish is known for. And instead of a firm, chewy interior, we wanted fish that was silky and moist, contrasting with the texture of the crust. By reducing the marinade time to between 6 and 24 hours, we found a window that allows you to achieve such a goal. A marinade composed of miso, sugar, mirin, and sake allows for flavor penetration, moisture retention, and better browning by drying the fish’s surface. Broiling the fish at a distance from the heating element allows for the fish to caramelize and cook evenly at the same time.
½ cup white miso paste
¼ cup sugar
3 tablespoons sake
3 tablespoons mirin
4 (6- to 8-ounce) skin-on salmon fillets
Note that the fish needs to marinate for at least 6 or up to 24 hours before cooking. Use center-cut salmon fillets of similar thickness. Yellow, red, or brown miso paste can be used instead of white.
1. Whisk miso, sugar, sake, and mirin together in medium bowl until sugar and miso are dissolved (mixture will be thick). Dip each fillet into miso mixture to evenly coat all flesh sides. Place fish skin side down in baking dish and pour any remaining miso mixture over fillets. Cover with plastic wrap and refrigerate for at least 6 hours or up to 24 hours.
2. Adjust oven rack 8 inches from broiler element and heat broiler. Place wire rack in rimmed baking sheet and cover with aluminum foil. Using your fingers, scrape miso mixture from fillets (do not rinse) and place fish skin side down on foil, leaving 1 inch between fillets.
3. Broil salmon until deeply browned and centers of fillets register 125 degrees, 8 to 12 minutes, rotating sheet halfway through cooking and shielding edges of fillets with foil if necessary. Transfer to platter and serve with lemon wedges.