Preheat the oven to 450ºF (230ºC). Place the salmon in a shallow ovenproof dish.
Whisk the syrup with the soy sauce and mustard. Pour over the salmon. Marinate for 10 minutes. Bake for 12 to 15 minutes or until opaque and cooked through.
Drizzle a small amount of syrup over each fillet. Sprinkle with sesame seeds and green onion (if using).
Tips:
For extra crunch, substitute chopped unsalted cashews for the sesames seeds.