Makes 4 servings

- Mussel Vinaigrette (see related recipe)

- 4 portions (6-ounces each) skinless halibut fillet

- Kosher salt and fresh ground pepper to taste

- 1½ tablespoons olive oil, divided

- 1 medium leek, white part only, sliced ¼-inch thick and rinsed

- 1 to 2 teaspoons water

- 1 tablespoon soft butter

- 2 teaspoons finely minced fresh rosemary

- 2 teaspoons finely minced fresh thyme

- 4 sprigs fresh thyme, for garnish

1. Be sure to make Mussel Vinaigrette in advance.

2. Preheat oven to 450 degrees. Season halibut with salt and pepper to taste. Heat 1 tablespoon olive oil in a large, heavy, oven-proof skillet over moderately high heat. Add halibut and cook on first side until golden brown, about 4 minutes. Turn fillets and cook 2 minutes more, until crispy and brown.

3. Place skillet in preheated oven and roast fish until just done through, about 3 to 4 minutes, depending on thickness of fillets.

4. Meanwhile, in a large nonstick sauté pan over medium-high heat, heat remaining olive oil until hot. Add the leeks and sauté 30 seconds; add the water and cook another 30 seconds, until just cooked and heated through.

5. Add Mussel Vinaigrette and heat until just warmed through. Remove pan from heat and swirl in the soft butter and fresh minced herbs.

6. When halibut is done, place each portion on a warm dinner plate. Divide leeks and mussels among the plates, and drizzle the warm vinaigrette over all. Garnish with fresh thyme sprigs.