Charring the plank also lends a unique depth of flavor to the salmon. My secret is spraying the salmon through the grilling process with Pinot Grigio wine to add more flavor and encourage some additional steaming of the plank!
Turn a gas grill to medium heat (250-300 degrees) or over medium heat charcoal, place the unsoaked plank on the grill. Leave the lid open and watch for the first wisps of smoke from the underside of the plank. Check the plank for singeing and char marks. Once they begin to appear (2-3 minutes), flip the plank over to do the same on the second side. Set aside.
Place the salmon fillet skin side down onto the charred plank. Sprinkle the top with the diced dill and cover with lemon slices. Place the plank on the grill over the unheated section of the grill. Spray 3-4 times with the wine (the wine landing on the plank will cause some steaming as well) and close the lid.
Check the internal temperature of the salmon at 20 minutes and every 5 minutes until the internal temperature registers 135-140 degrees. Remove and allow to rest for 5 minutes. Cut into 4 portions by cutting across the fillet.