Halibut À LA Nage with Clams, Dill, and White Wine

Ingredients

• 4 tablespoons unsalted butter, divided
• 1 medium yellow onion, diced
• 1 small fennel bulb, halved, cored, and diced, plus fronds for garnish, optional
• 2 medium cloves garlic, roughly chopped
• 1 stalk celery, diced
• 1 cup dry white wine
• 2 cups water
• 4 skinless halibut fillets
• Kosher salt and freshly ground black pepper
• 1 dozen littleneck clams, scrubbed
• 1 tablespoon chopped dill

Directions

1. Warm 2 tablespoons butter in a large, straight-sided sauté pan over medium-high heat until it bubbles and foams. Stir in the onion, diced fennel, garlic, and celery, and cook until the vegetables have softened and the onion looks clear, about 3 minutes.
2. Pour in the wine and continue cooking, stirring as it reduces by about half and loses most of its sharp raw-alcohol smell, about 4 minutes. Add the water.
3. Sprinkle the halibut fillets with salt and pepper, then tuck them into the liquid so they are partly covered. Arrange the clams in the broth around the fish. Bring the liquid to a gentle simmer, cover the pan, and turn the heat down. Cook with the lid on until the clams have opened and the halibut is just cooked through, reaching 135 degrees F on an instant-read thermometer, about 5 minutes.
4. With a slotted spatula, move the fish and clams into bowls. Whisk the dill and the remaining butter into the broth until the butter has melted completely and blended in. Taste the broth and season with salt and pepper, then spoon it, along with the vegetables, around the fish and clams. Finish with fennel fronds, if desired, and serve right away.