In a bowl, combine the pepper, paprika, thyme, mustard, salt, and cayenne. Brush both sides of the fish with 2 tsp. of the oil and gently rub the spice mix all over the fish.
In a small skillet, heat the butter over medium heat, swirling the skillet, until the butter is a deep amber brown, about 3 minutes; watch carefully so it doesn’t burn. Whisk in the lemon juice and keep warm.
Set a heavy nonstick skillet over medium-high heat and heat 1 Tbs. of the oil. When the oil is hot, add two of the fillets and sear until cooked through, about 2 minutes. per side; transfer to a plate and tent with foil. Wipe out the pan and repeat with the remaining oil and fish. Serve immediately, spooning the butter over the fish.
Serve with couscous tossed with herbs, red peppers, and-scallions.
nutrition information (per serving):
based on four servings;
Photo: Scott Phillips