fish pie with leeks + potatoes

Fish pie is a traditional British dish that’s similar to a shepherd’s pie, and simply put, is pure comfort food in a bowl. Velvety mashed potatoes blanket a casserole of fish baked in an herbed cream sauce until bubbly. The pie is usually made with white fish but salmon also works, or a combination of both.

1 1/2 pounds skinless cod fillets (or similar), cut into 1-inch pieces

Mashed Potatoes
6 medium Yukon gold potatoes
Kosher salt, to taste
2-4 tablespoons unsalted butter
1/2 cup milk (or cream)
Freshly ground black pepper, to taste

2 tablespoons unsalted butter, divided
1 shallot, minced
1 leek, white and light green parts, trimmed and chopped
1 clove garlic, finely minced
1/4 cup flour
1/2 cup white wine
1 cup milk or cream
1 tablespoon Dijon mustard
2 tablespoons minced fresh chives
1 cup grated cheddar cheese, optional

  1. Pat fish completely dry and set aside.
  2. Make mashed potatoes. Peel and dice potatoes and add to a large saucepan with enough cold water to cover. Add a pinch of salt and bring to a boil; reduce heat and simmer until potatoes are fork-tender, 30-40 minutes. Drain potatoes and place back in saucepan. Add 2 tablespoons butter and 1/4 cup milk (or cream) to potatoes and mash until combined using either a hand mixer or a potato masher. Season with salt and pepper. Add more butter or milk if necessary to reach desired consistency. Set aside.
  3. Preheat oven to 375°F. Coat bottom and sides of a 9-inch baking pan with 1 tablespoon butter. Place on a large baking sheet and set aside.
  4. Place leeks in a sieve and rinse under cold water several times to remove dirt. Pat completely dry and set aside.
  5. In a large saucepan, melt remaining 1 tablespoon butter over medium heat. Add shallots and leeks and cook until slightly softened, 5-10 minutes. Season with salt and pepper. Add garlic and cook for another 1-2 minutes. Add flour and stir until incorporated into vegetables, about 1 minute. Slowly pour in wine and stir to combine, scraping up any browned bits on bottom of pan. Cook for another 1 minute. Add milk or cream, mustard, and chives and cook for another 1-2 minutes, until sauce is thickened. Remove from heat.
  6. Scatter fish evenly over bottom of pan, then pour in sauce, leveling it out evenly over fish in pan. Top entire mixture with an even layer of mashed potatoes. Sprinkle top with cheese (if using) and season with salt and pepper. Bake until cooked through and bubbly, about 30-40 minutes. Remove from oven and allow to cool for 5 minutes before serving.

Serves 4-6.

cook’s note: This can also be made in individual casserole dishes.