Preheat oven to 400°.
Combine first 5 ingredients in a shallow dish. Dredge both sides of salmon in peppercorn mixture.
Heat a large ovenproof skillet over medium heat. Coat pan with cooking spray. Add salmon; cook 2 minutes on each side. Bake at 400° for 6 minutes or until fish flakes easily when tested with a fork or until desired degree of doneness. Drizzle fillets evenly with soy sauce.