There aren’t that many slow cooker fish recipes out there, but this slow cooker Fish Pie is one of the best, made with 800 grams of mixed fish, 50 grams of butter, 450 milliliters of milk, and 50 grams of plain flour, ready to delight your taste buds.

To make your Fish Pie in the slow cooker, start by softening the leeks in spray oil, then create a roux with butter and flour, gradually add milk and stock, pour over the fish, and cook on low for 2-3 hours.

So follow me and let’s try one of my favourite slow cooker recipes. It’s a guaranteed crowd-pleaser that’s easy to make and packed with flavor!

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What is Fish Pie?

Fish Pie is a traditional British dish, celebrated for its comforting and hearty qualities. It typically features a creamy blend of mixed fish such as salmon, smoked haddock, and unsmoked haddock, enveloped in a rich sauce made with butter, milk, and flour. The pie is crowned with a layer of mashed potato before being baked to golden perfection.

Can I use frozen fish for this Fish Pie recipe?

Yes, you can use frozen fish for this Fish Pie recipe. Ensure the fish is fully thawed and patted dry before use to maintain the dish’s texture and flavor. This approach works well with a mix of salmon and haddock, totaling 800 grams.

Slow Cooker Fish Pie Ingredients

• Spray oil (for coating)
• 1 leek, thinly sliced (to add a mild onion-like flavor)
• 50 grams of butter (adds richness)
• 50 grams of plain flour (for thickening the sauce)
• 450 milliliters of milk (the base for the sauce)
• 150 milliliters of fish or chicken stock (for additional flavor)
• 75 grams of cheese, grated (for creamy texture and taste)
• 1 bay leaf (for an aromatic touch)
• 800 grams of mixed fish (such as salmon, smoked haddock, and unsmoked haddock), skinned and cubed (the star of the dish)

For the Topping:

• 800 grams of mashed potato, made with milk and butter for richness. Alternatively, for a lighter version, you can use just skimmed milk.

How To Make Slow Cooker Fish Pie

1. Prepare the Leeks: Coat a large saucepan with spray oil and fry the leeks on medium heat until they are softened. This should take about 5 minutes. Once softened, remove the leeks from the saucepan and set them aside on a plate.
2. Make the Sauce: In the same saucepan, melt 50 grams of butter over medium heat. Then, sprinkle in 50 grams of plain flour and pour in 450 milliliters of milk gradually. Whisk constantly while bringing the mixture to a boil to avoid lumps. Continue whisking until the sauce thickens and becomes smooth, which should take around 5 minutes. Stir in 150 milliliters of fish or chicken stock, 75 grams of grated cheese, and a bay leaf for an extra layer of flavor.
3. Assemble in Slow Cooker: Place the cubed fish in an even layer at the bottom of your slow cooker pot. Scatter the previously softened leeks over the fish. Then, carefully pour the prepared sauce over the leeks and fish, ensuring an even distribution.
4. Cooking Time: Cover the slow cooker and set it to cook on low for 2-3 hours. The fish should be perfectly tender and the flavors well blended by the end of cooking.
5. Add the Topping: Preheat your oven to 200°C (392°F). Spoon the fish mixture into an ovenproof dish. Cover the fish mixture evenly with 800 grams of mashed potato. For a golden, crispy top, sprinkle additional grated cheese over the mashed potato.
6. Browning: Place the dish in the oven and bake until the topping turns golden and slightly crispy, approximately 20-25 minutes.

Recipe Tips

• Even Fish Pieces: Cut the fish into even-sized pieces to ensure uniform cooking. Consistency in size helps every bite to be perfectly tender, enhancing the overall texture and flavor of the pie.
• Sauce Consistency: Aim for a sauce that’s thick enough to cling to the fish but not too dense. If the sauce is too thin, the pie may end up watery. If it’s too thick, it might not spread as nicely.
• Seasoning Layers: Season each layer of your dish – the fish, the sauce, and the mashed potatoes. Proper seasoning at each stage builds depth of flavor, ensuring the pie is flavorful from top to bottom.
• Mashed Potato Texture: For the topping, use creamy, well-seasoned mashed potatoes. They should be smooth enough to spread easily but firm enough to hold up in the oven. This balance provides the perfect crown for your fish pie.

Recipe Variations

• Creamy Mustard Twist: Stir in 2 tablespoons of wholegrain mustard into the sauce for a tangy, creamy flavor. This addition elevates the dish, adding depth and a slight bite that perfectly complements the fish.
• Crunchy Topping: Mix breadcrumbs with grated Parmesan cheese and sprinkle over the mashed potato layer before baking. This variation introduces a delightful crunch, offering a textural contrast to the soft fish and creamy potatoes.
• Luxury Seafood Addition: Incorporate prawns, scallops, or crab meat into the fish mix for a luxurious upgrade. Adding these seafood elements transforms the pie into a gourmet experience, perfect for special occasions.
• Vegetable Boost: Fold in a cup of peas and diced carrots with the fish before adding the sauce. This not only adds color and nutrition but also enhances the pie with sweet, earthy flavors, making it a more rounded meal.

What To Serve With Your Fish Pie

Serve your Fish Pie with sautéed spinach, sweet potato fries, garlic-roasted asparagus, steamed broccoli, and a fresh green salad. These sides complement the pie’s flavors, adding texture and color to your meal.

How To Store Fish Pie

In The Fridge:

Cool the Fish Pie completely before covering it with plastic wrap or transferring it to an airtight container. Store in the fridge for up to 3 days. Ensure it’s sealed well to maintain freshness and prevent absorbing other food odors.

In The Freezer:

Fish Pie can be frozen for up to 2 months. Cool it completely, wrap securely in foil or place in a freezer-safe container. Label with the date. Thaw overnight in the fridge before reheating.

How To Reheat Fish Pie

Reheat your Fish Pie in the oven at 350°F (175°C) for 20-25 minutes, or until thoroughly heated through. Ensure it’s covered with foil to prevent drying out.

Check out More Slow Cooker Recipes:

• Slow Cooker Steak And Mushroom Pudding
• Slow Cooker Goat Stew
• Slow Cooker Cheeseburger Pasta