Braised Halibut with Leeks and Mustard

Our braising method for fish delivers perfectly cooked fillets along with a vegetable side and silky sauce.

Braised Halibut with Leeks and Mustard
WHY THIS RECIPE WORKS When it comes to methods for cooking fish, braising is often overlooked. But this approach, which requires cooking the fish in a small amount of liquid so that it gently simmers and steams, has a lot going for it. As a moist-heat cooking method, braising is gentle and thus forgiving, all but guaranteeing tender fish. Plus, it makes a great one-pot meal since the cooking liquid becomes a sauce, and it’s easy to add vegetables to the pan to cook at the same time. We chose halibut for its sweet, delicate flavor and firm texture that made for easier handling and paired it with the classic French flavors of leeks, white wine, and Dijon mustard. Because the portion of the fillets submerged in liquid cooks more quickly than the upper half that cooks through in the steam, we cooked the fillets for a few minutes in the pan on just one side and then braised them parcooked side up to even out the cooking. For the cooking liquid, wine supplemented by the juices released by the fish and vegetables during cooking delivered a sauce with balanced flavor and just the right amount of brightness. If halibut isn’t available, you can substitute sea bass in this recipe.

4 (4- to 6-ounce) skinless halibut fillets, ¾ to 1 inch thick
Salt and pepper
¼ cup extra-virgin olive oil, plus extra for serving
1 pound leeks, white and light green parts only, halved lengthwise, sliced thin, and washed thoroughly
1 teaspoon Dijon mustard
¾ cup dry white wine
1 tablespoon minced fresh parsley
Lemon wedges

1. Pat halibut dry with paper towels and sprinkle with ½ teaspoon salt. Heat oil in 12-inch skillet over medium heat until warm, about 15 seconds. Place halibut skinned side up in skillet and cook until bottom half of halibut begins to turn opaque (halibut should not brown), about 4 minutes. Carefully transfer halibut raw side down to large plate.
2. Add leeks, mustard, and ¼ teaspoon salt to oil left in skillet and cook over medium heat, stirring frequently, until softened, 10 to 12 minutes. Stir in wine and bring to simmer. Place halibut raw side down on top of leeks. Reduce heat to medium-low, cover, and simmer gently until halibut flakes apart when gently prodded with paring knife and registers 140 degrees, 6 to 10 minutes. Carefully transfer halibut to serving platter, tent loosely with aluminum foil, and let rest while finishing leeks.
3. Return leeks to high heat and simmer briskly until mixture is thickened slightly, 2 to 4 minutes. Season with salt and pepper to taste. Arrange leek mixture around halibut, drizzle with extra oil, and sprinkle with parsley. Serve with lemon wedges.

Braised Halibut with Carrots and Coriander
Substitute 1 pound carrots, peeled and shaved with vegetable peeler into ribbons, and 4 shallots, halved and sliced thin, for leeks. Substitute ½ teaspoon ground coriander for Dijon mustard and stir 1½ teaspoons lemon juice into carrot mixture before seasoning with salt and pepper. Substitute 1 tablespoon minced fresh cilantro for parsley.

Braised Halibut with Fennel and Tarragon
Substitute two 10-ounce fennel bulbs, stalks discarded, bulbs halved, cored, and sliced thin, and 4 shallots, halved and sliced thin, for leeks. Omit Dijon mustard and stir 1 teaspoon lemon juice into fennel mixture before seasoning with salt and pepper. Substitute 1 tablespoon minced fresh tarragon for parsley.