1 salmon fillet, C\v-inch thick, skin removed (1Z\x to 2 lbs.)1 15-by-6½ by 3/8-inch cedar or alder grilling plank, soaked in water for at least 1 hourFor the slather½ cup Dijon mustard½ cup mayonnaise1 tsp. chopped fresh dill1 clove garlic, mincedZest and juice of ½ lemonPrepare an indirect fire in a grill, with a hot fire on one side and no fire on the other.To make the slather, combine all the ingredients in a small bowl until smooth.Compare the length of the plank with the length of the salmon fillet and trim the salmon to fit the plank, if necessary. Place the salmon on the prepared plank and spread the mustard slather over the top.Place the plank on the grill grate on the no-heat side. Cover the grill and cook until the fish begins to flake when tested with a fork in the thickest part, 25 to 30 minutes. Serve the salmon hot, right from the plank.From "Techniques for Grilling Fish" Karen Adler and Judith Fertig