Soak plank in water to cover 3 hours; drain.
Process coriander seeds and whole red peppers in a food processor 1 minute or until finely crushed. Add kosher salt and next 4 ingredients; process 5 seconds.
Rub seasoning mixture on flesh side of salmon. Wrap salmon in heavy-duty plastic wrap, and chill 3 hours.
Place seasoned salmon on plank. Grill, covered with grill lid, over medium-high heat (350° to 400°) 27 minutes or until fish flakes with a fork.