Preheat your oven to 400°F (200°C) for a beautiful, caramelized finish.
Rinse the salmon filets under cold water and pat them dry. Place skin-side down on a baking sheet lined with parchment paper and season with salt and pepper.
In a mixing bowl, combine miso paste, soy sauce, brown sugar, rice vinegar, and sesame oil. Mix until smooth.
Spoon the miso glaze over the salmon filets and let them marinate for about 10 minutes.
Bake the salmon for 12-15 minutes, or until it flakes easily with a fork.
Remove from oven, garnish with green onions and sesame seeds, and serve immediately.