1.Combine glaze ingredients soy sauce, sake, brown sugar, rice vinegar, green onion, and ginger in a bowl and stir until brown sugar is completely dissolved.
2.Rinse and pat dry salmon fillets. Place salmon fillets in glaze and marinate for a few minutes, and then flip over and marinate for a couple more minutes.
3.Heat oil in a large saute-pan over high heat. Sear salmon in hot pan, turning once, until browned but barely cooked through, about 3 minutes each side.
4.While salmon cooks, place glaze in a small saucepan. Bring to a simmer over high heat. Vigorously simmer for 5 minutes.
5.Plate salmon and brush or pour glaze over salmon.