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Delicious Fish Pie with Mashed Potato Top: A Recipe to Use What You Have

5 min read·5/27/2026·Main dish·FridgeChef
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20 min
Ingredients
  • **For the Filling:**
  • 500g white fish fillets (cod, haddock, pollock), or a mix of fish and salmon
  • 100g smoked haddock (optional, for extra flavour)
  • 1 tbsp butter or oil
  • 1 onion, finely chopped
  • 2 carrots, diced
  • 100g frozen peas
  • 2 tbsp plain flour
  • 400ml milk (any kind)
  • 1 tbsp chopped fresh parsley or dill (optional)
  • Salt and freshly ground black pepper to taste
  • A squeeze of lemon juice (optional)
  • **For the Mashed Potato Topping:**
  • 1kg potatoes, peeled and quartered
  • 50g butter
  • 50-100ml milk (warm)
  • Salt and pepper to taste
  • Grated cheese (cheddar or parmesan, optional)

From Fridge to Feast: Your Ultimate Fish Pie Recipe

Ever find yourself staring into the fridge, wondering what to make with those leftover bits of fish? Our Fish Pie with Mashed Potato Top is the perfect solution! This comforting classic is designed to be flexible, allowing you to use whatever fish you have on hand, be it cod, haddock, salmon, or a mix. It’s a fantastic way to reduce food waste and create a truly satisfying meal.

Step-by-Step Deliciousness

  1. Prepare the Potatoes: Place the peeled and quartered potatoes in a large pan, cover with cold water, add a pinch of salt, and bring to the boil. Cook for 15-20 minutes, or until tender. Drain well and return to the pan over low heat for a minute to dry out any excess moisture.
  2. Mash Away: Add the butter and warm milk to the potatoes. Mash until smooth and creamy. Season with salt and pepper. Stir in grated cheese if using. Set aside.
  3. Sauté the Veggies: While the potatoes are cooking, melt the butter or heat the oil in a large, ovenproof saucepan or frying pan over medium heat. Add the chopped onion and diced carrots and cook for 5-7 minutes until softened.
  4. Make the Sauce: Stir in the flour and cook for 1 minute, stirring constantly. Gradually whisk in the milk until you have a smooth sauce. Bring to a simmer and cook for 2-3 minutes until thickened.
  5. Add the Fish and Peas: Gently flake the fish into the sauce (if using smoked haddock, flake that in too). Stir in the frozen peas. Cook for just 2-3 minutes until the fish is heated through and starting to flake. Be careful not to overcook the fish. Stir in the fresh herbs and lemon juice if using. Season with salt and pepper.
  6. Assemble the Pie: Preheat your oven to 200°C (180°C fan/Gas Mark 6). Spoon the fish mixture evenly into an ovenproof dish if your pan isn't ovenproof. Carefully spoon or pipe the mashed potato over the fish mixture, spreading it to cover completely and sealing the edges.
  7. Bake to Perfection: Place the dish on a baking tray (to catch any spills) and bake for 20-25 minutes, or until the topping is golden brown and the filling is bubbling.

Tips for the Best Fish Pie

  • Fish Variety: Don't be afraid to mix different types of fish for a more complex flavour. Prawns or mussels can also be added.
  • Creamy Sauce: For an even richer sauce, use half milk and half double cream.
  • Herbs: Fresh dill or chives work wonderfully in fish pie.
  • Crispy Topping: For a crispier mash, rough up the surface with a fork before baking, or add a sprinkle of breadcrumbs mixed with a little melted butter.
  • Make Ahead: You can assemble the pie and refrigerate it before baking. You may need to add a few extra minutes to the baking time.

Ready to Cook?

This recipe is a testament to the magic of home cooking. By utilizing ingredients you already have, you can whip up a meal that’s both economical and incredibly delicious. Give this Fish Pie with Mashed Potato Top a try tonight and discover how easy it is to create a satisfying dish from your own kitchen!

Frequently Asked Questions

  • Q: Can I use frozen fish for this recipe? A: Yes, you can use frozen fish. Ensure it is fully defrosted and patted dry before adding it to the sauce.
  • Q: What if I don't have any onions or carrots? A: You can omit them or substitute with other vegetables like leeks, celery, or frozen mixed vegetables.
  • Q: Can I make this vegetarian? A: While this is a fish pie, you could adapt the concept using a creamy vegetable filling with a mashed potato topping.
  • Q: How long does the mashed potato topping last? A: Mashed potato topping is best used fresh, but leftovers can be stored in the refrigerator for 1-2 days and reheated.
  • Q: Can I freeze the assembled fish pie? A: It's generally not recommended to freeze fish pie once assembled, especially with the mashed potato topping, as the texture can be affected upon thawing and reheating.
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