Salmon fillets marinaded in miso paste and grilled in a frying pan
Mix miso, mirin, sake, and sugar in a bowl. Marinate salmon fillets in the miso mixture for at least 3 hours, or overnight.
Carefully wipe excess marinade from the salmon fillets.
If using an oven: Preheat oven to 450°F. Line a baking sheet with aluminum foil, lightly oil it, and bake for 10-12 minutes.
If cooking on the stovetop: Heat a nonstick frying pan with a touch of oil over low heat. Place salmon fillets in the pan and cook until nicely browned on both sides.