Heat a 14-inch saute pan to medium high. Dry the skin side of the filets with a cloth. Generously season both sides of the fish with salt and white pepper. Add the clarified butter to the pan and place 3 of the fillets in the pan skin side down. Cook for 3 minutes and gently turn using a fish spatula. Cook an additional 2 minutes and reserve on absorbent cloth. Cook the other fillet in the same fashion. Wipe the hot pan out with a dry clean cloth. Add the cold butter to the pan and swirl around. Allow the butter to brown. Carefully add the crabmeat to the pan and use a wooden spoon to gently stir the pan. Add the lemon juice and parsley. Remove from the heat.
In a medium mixing bowl, combine the warm mushrooms and their oil with the watercress. Place some of the mixture on a plate. Place fillet of fish skin side up on top of the salad and top with a generous amount of the crab meat mixture.
ROASTED SHIITAKE MUSHROOMS:
Preheat the oven to 425 degrees. In a large bowl, toss together the mushrooms, garlic, herbs, olive oil and salt and pepper. Place the mushrooms on a baking sheet and bake for 15 minutes.