In a small bowl, whisk collectively soy sauce, orange juice, mustard, cayenne pepper, ginger, garlic, and honey. Place salmon fillets in a big zip-top bag and drizzle evenly with marinade. Seal bag and shake gently to coat fish. Marinate within the fridge for 1 hour, turning sometimes.
Preheat grill to medium-high warmth (round 350°F). Place salmon on the grill, reserving marinade. Baste fish with marinade, then grill about 6 minutes on all sides, or till fish flakes simply when pierced with a fork. Carry remaining marinade to a boil and boil 2–3 minutes. (Don’t use remaining marinade until it’s boiled). Drizzle cooked salmon with heated marinade and prime with toasted sesame seeds.
