Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper for easy cleanup.
In a small bowl, whisk together the miso paste, mirin, soy sauce, and sesame oil until smooth and well combined. This creates a glossy, flavorful glaze that will caramelize beautifully.
Place the salmon fillets on the prepared baking sheet, skin-side down if applicable, and pat them dry with a paper towel to ensure crispy edges.
Using a spoon or brush, evenly spread about two-thirds of the miso mixture over the top of each fillet, coating them generously with the glaze. Reserve the remaining glaze for later use or serving.
Place the baking sheet in the oven and bake for 12–15 minutes, or until the salmon is cooked through and the surface is golden and slightly caramelized, with a gentle crackle as the glaze sets.
Once baked, remove the salmon from the oven and let it rest for a couple of minutes; this helps the juices redistribute and the glaze to firm up slightly.
Serve the miso salmon hot, with any remaining glaze drizzled over the top, and enjoy its crispy, tender texture and rich flavor.
