This slow cooker fish pie is my ultimate cozy-night dinner—it’s warm, creamy, and oh-so-satisfying. I love how the buttery mash on top browns up perfectly under the grill, giving it a crisp finish over the rich, creamy filling. The pollock and prawns add the perfect touch of fresh seafood flavor.

A tip? Try making it a day ahead; it’s even better after the flavors have had time to settle. Pair it with a simple salad or your favorite veggie side, and you’ve got a meal that feels both hearty and special.

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Recipe Ingredients

• 400 ml full-fat milk
• 50 g butter, plus extra for dotting
• 50 g plain flour
• 1 onion, finely chopped
• 2 bay leaves
• 1 good grating of nutmeg
• 700 g pollock fillet, skinned and cut into bite-sized pieces
• 300 g raw peeled North Atlantic prawns
• Small bunch of parsley, chopped

For the Mash

• 1 kg floury potatoes, peeled and chopped into chunks
• 50 ml full-fat milk
• 25 g butter
• Pinch of freshly grated nutmeg

How To Make Slow Cooker Sustainable Fish Pie

1. Prepare the Sauce Base: Heat the slow cooker if needed. In a saucepan, warm the milk until it’s almost boiling, then pour it into the slow cooker. Mix the butter and flour into a paste in the slow cooker pot, gradually whisking in the milk until smooth. Add the onion, bay leaves, nutmeg, salt, and pepper, then cover and cook on High for 3 hours, stirring every hour.
2. Add the Seafood: After 3 hours, add the pollock pieces, prawns, and chopped parsley to the sauce, making sure they are well-coated. Cover again and cook on High for an additional 30 minutes, or until the seafood is just cooked.
3. Prepare the Mashed Potatoes: While the fish mixture cooks, boil the potatoes in salted water until they are fork-tender. Drain the potatoes well, then return them to the pot. Add the milk, butter, and nutmeg, then mash until smooth, seasoning with salt and pepper to taste.
4. Assemble the Pie: Preheat the grill to medium-high heat. If your slow cooker pot isn’t safe for grilling, transfer the fish mixture to an ovenproof dish. Spoon the mashed potatoes evenly over the fish mixture, spreading it to cover the surface completely.
5. Finish with Butter and Grill: Dot the top of the mashed potatoes with small pieces of butter. Place the dish under the grill and cook until the top is golden brown and crisp.
6. Serve the Fish Pie: Serve the fish pie hot, spooning generous portions of the fish and mash onto each plate, making sure each portion is layered with creamy fish and golden mash.

Recipe Tips

• For a creamier texture in the sauce, try adding 1/4 cup of heavy cream during the last hour of cooking. It adds extra richness and a velvety finish to the fish pie.
• Swap pollock for another white fish like cod or haddock if that’s what you have on hand. These options maintain the dish’s mild flavor and flake beautifully when cooked.
• To add a touch of zest, stir in a teaspoon of lemon zest or a squeeze of lemon juice with the parsley. It brightens up the dish with a refreshing hint of citrus.
• If you prefer a dairy-free option, substitute the milk with a plant-based milk alternative and the butter with olive oil or vegan butter for a similar texture.

Recipe FAQs and Variations

Check out More slow cooker pie Recipes:

• Slow Cooker Chicken and Vegetable Pie
• Slow Cooker Chicken And Leek Pie
• Slow Cooker Steak And Mushroom Pudding
• Slow Cooker Steak and Guinness Pie