Prep the pan: Line a sheet pan with foil and lightly oil it, or use parchment. Set the oven to 400°F (205°C).
For extra caramelization, plan to switch to broil at the end.
Make the glaze: In a small bowl, whisk miso, honey, soy sauce, rice vinegar, sesame oil, ginger, garlic, and sriracha (if using) until smooth. The mixture should be thick but spreadable.
Season the salmon: Pat fillets dry. Lightly season with salt and pepper.
Go easy on the salt—miso and soy are already salty.
Coat the fish: Place salmon skin-side down on the pan. Brush or spoon a generous layer of glaze over the tops and sides. Reserve a spoonful for a quick touch-up after baking.
Roast: Bake for 8–10 minutes, depending on thickness.
A general guide is about 4–6 minutes per 1/2 inch of thickness.
Broil for gloss: Switch the oven to broil and cook 1–2 minutes more to caramelize the glaze. Watch closely—it goes fast.
Check doneness: The salmon should flake easily with a fork and be just opaque in the center. Target an internal temperature of 125–130°F (52–54°C) for medium.
Finish and serve: Brush with the reserved glaze for shine.
Sprinkle with sesame seeds and scallions. Serve with lime or lemon wedges.