Grind the peppercorns, cayenne pepper, paprikas, herbs, and sea salt in a mortar and pestle. Add garlic, and rub into the salmon flesh. Let this sit, up to 30 minutes, until the plank has been soaked. Mix the honey and either rice vinegar or balsamic vinegar (either is really good), and set aside.
If you are using the oven, put the plank on a cookie sheet or piece of foil, and heat the plank for 5 minutes in the oven. Then, in either case, put the salmon, skin side down, on the plank. Brush the vinegar-honey mixture on the salmon, and place in the oven or on the preheated grill. Cook about 10 minutes. Check for doneness by cutting into the thickest part of the salmon. Cook until the fish is barely opaque all the way through. Please do not overcook. You can serve the salmon on the plank or on a serving tray.
If you use the grill, the plank will be charred, and cannot be re-used. If you use the oven, the plank can be washed and used again 3 or 4 times. If the plank catches fire in the grill, just splash with a bit of water.
The salmon can be served either warm or cold. If chilling before serving, keep the salmon on the plank, wrapped well in foil. Just before serving, place the filet on a large serving tray, and baste with any residual cooking juices.