Place the leeks, carrot, celery, wine, and broth in a microwave-safe baking dish. Sprinkle the shark with the salt and pepper, and add it to the dish. Cover the dish with a microwave-safe lid or with plastic wrap turned up at one corner to allow the steam to vent. Place the dish in the microwave oven, and cook the fish on high for 12 minutes or until it is cooked through, giving the dish a quarter turn after 6 minutes if your microwave oven does not revolve.

With a slotted spoon, remove the fish to a platter, leaving behind the vegetables, and cover the fish with foil to keep it warm.

Stir the couscous, peas, and salt to taste (if desired) into the vegetables and their liquid in the baking dish, cover the mixture tightly, and allow it to sit for 5 minutes or until all the liquid has been absorbed.

Place an ample serving of couscous on each of 4 plates, distributing the couscous so that it covers most of the dish. Place two pieces of fish on top of each serving of couscous, sprinkle the fish and couscous with the parsley, and garnish each plate with a lemon wedge.