Soak the wood plank! Whatever you use to soak the plank, make sure it’s fully submerged in water and soak for 1-2 hours.
Rub bottom of the salmon skin with some oil.
Whisk ingredients for the mustard sauce and rub salmon all over the top and sides. Set it aside until ready to put on the plank to grill.
Preheat the grill to medium with a two-zone fire just in case. Place soaked wood planks on the grill and heat it up for about 5 minutes.
Flip the planks and place salmon on it, skin down.
Close the lid and cook salmon until it’s done. I prefer to cook it until it reaches 135° in the thickest part.
(Note: USDA recommends salmon safe temperature to be 145° but many people feel that it is overdone.) Depending on the thickness of salmon piece, it could take from 12-20 minutes. A whole salmon filet that is thick could take well over 20 minutes. You will have to check the temperature with an instant read thermometer.
Disclaimer: Nutrition information shown is not guaranteed to be 100% accurate as most ingredients and brands have variations.