Soak plank in water one hour prior to use. Drain.
Combine vinegar and next 6 ingredients in large Ziploc bag, seal and shake to combine. Add salmon, reseal and marinate in refrigerator for 30 minutes, turning once.
Place plank on grill for 5 min. or until slightly charred.
Carefully turn plank over and move to cool side of grill. Place fish, skin side down, on charred side of plank.
Cover and grill for 15 min. or until fish flakes easily when tested with a fork.
Sprinkle with onions and sesame seeds and serve.