Easy Creamy Fish Pie With Spinach

6 servings
50 min

· Print Recipe

This Easy Creamy Fish Pie With Spinach is a classic British comfort dish where flaky cod, smoked haddock, prawns and spinach are combined in a herby, zesty and creamy sauce. This is finished with fluffy mash and a scrumptious grilled cheese topping that is sure to leave you wanting more.

This is a delicious, but also straightforward and everyday fish pie that uses easy-to-find ingredients. Fish pie is a dish that is very hard to do quickly and do well, but I have tried to make the process as streamlined and fuss-free as possible without compromising taste. This fish pie recipe will take around an hour to make, which is not super quick, but also far from the longest I have spent making a fish pie. What's great is that fish pie can be frozen for up to 3 months so is a great dish to batch cook and freeze for later.

fish pie with spinach plated and served
Key ingredients and possible alternatives:

  • Mashed potato - Maris Piper or any other variety of potatoes that are good for mashing will work well. King Edward or Russet are good alternatives.
  • Spinach - I always use fresh spinach but you could also use frozen spinach. Either way, you need to make sure you drain as much water from it as possible. Watery spinach will alter the consistency of the sauce.
  • Fish - I have suggested equal portions of smoked haddock, cod and prawns. You can substitute any of these fish as desired as long as you keep the volume the same. You can use frozen or fresh fish but make sure frozen fish is defrosted first and any moisture is removed with kitchen paper before you fry it. Use skinless fish if possible. If your fish has skin on I recommend frying the fish whole and removing the skin before you cut it into small chunks. If you are using raw prawns I advise butterflying and deveining first. This helps them to absorb the flavour of the sauce and removes the intestinal tract.
butterflied prawn with the intestinal tract removed
  • Sauce - butter and flour are cooked on a medium heat to form a roux and then milk is added to form the sauce. Fish stock reduces the thickness of the sauce and also adds a salty fish taste. You could substitute fish stock for vegetable or chicken stock, this would still bring saltiness but would not add a fish flavour.
  • Cheesy Topping - I use a combination of cheddar and Parmesan because I like the nutty tanginess it brings to the topping. You could just use cheddar or any other hard cheese. I add a handful of dried breadcrumbs to the topping to bring an additional crunch. This is optional but highly recommended.
spinach fish pie ingredients
How to make Easy Fish Pie with Spinach

1. Boil the potatoes

Bring a pan of generously salted water to boil, reduce to a simmer and add the chopped and peeled potatoes and boil for 15 to 20 minutes until you can easily place a fork through them. You can continue to prepare the spinach, fish and sauce while the potatoes are cooking. I recommend setting a timer so you do not forget about the potatoes.

2. Wilt the spinach

Place a large frying pan on a medium heat, add the washed spinach and cook until wilted. You might need to do this in two batches. When the spinach is ready drain it with a colander to remove any excess moisture. Adding watery spinach to the sauce will make it thinner, alter the consistency and make it less flavourful.

wilted spinach in a pan

3. Cook the fish

You can use the same pan you used to cook the spinach, just wipe it out with some kitchen paper first. Place the pan on a medium heat, add the oil and fry the pieces of haddock and cod until they are opaque. Remove them from the pan and set them aside and add the prawns and cook for a couple of minutes until they are opaque. Set them aside with the haddock and cod when they are ready.

cooked cod, haddock and prawns

4. Make the sauce

Wipe the pan again and place it on a medium heat and melt the butter. Stir in the flour to form a roux and gradually add the milk. Stir continuously until a thick source is formed then gradually stir in the fish stock. Add the garlic clove and season the sauce with lemon juice, lemon zest, ground nutmeg, fresh dill and chives and ground black pepper. Stir in the fish and spinach and leave the sauce on your stove's lowest heat while you mash the potatoes.

Fish pie sauce

5. Mash the potatoes

Add butter, milk and pepper to the boiled potatoes and mash until smooth and fluffy. Add a little salt to taste if needed.

mashed potatoes

6. Assemble the fish pie

Add the sauce mixture into a baking dish and spoon the mashed potato on top. Sprinkle grated cheese onto the mash and add breadcrumbs if using. Grind a little black pepper over the top of the pie.

fish pie assembled and ready to be baked

7. Bake in the oven

Bake the fish pie in the oven for approximately 15 minutes until the topping is brown and the filling is bubbling around the edges. Place the fish pie under the grill for a couple of minutes to get the topping extra brown and crispy (optional but highly recommended).

baked fish pie
Tools and equipment

  • Potato peeler - for prepping the potatoes.
  • Sharp knife - for cutting the potatoes and fish.
  • Large saucepan - choose a pan that is large enough for boiling the potatoes.
  • Colander - for draining the potatoes and spinach.
  • Large frying pan - choose a frying pan that is large enough to hold the sauce. I like to use a cast iron pan because it retains an even heat, but any large frying pan will be sufficient. You can use the same pan to wilt the spinach, fry the fish and make the sauce. Make sure you wipe it clean with kitchen paper in between.
  • Potato masher - necessary for achieving a fluffy and smooth mashed potato topping.
  • Cheese grater - for grating the cheese for the topping. You can also buy pre-grated cheese if you prefer.
  • Baking dish - I use 27 x 16cm cast iron baking dish.

Three tips for a perfect Easy Creamy Fish Pie With Spinach

  1. Set a timer for the potatoes - you can wilt the spinach, fry the fish and make the sauce while the potatoes are boiling but make sure you do not forget about them and let them overcook.
  2. Remove water from the spinach - add the spinach to a colander once wilted and use your hands to gently squeeze out any remaining water over the sink. This will ensure that you do not add additional liquid to the sauce.
  3. Crisp up the topping once the fish pie has baked - place the baked fish pie under the grill for a couple of minutes to get the cheesy topping extra brown and crispy.
baked fish pie ready to serve
Serving suggestions

I always serve my fish pie with petit pois or garden peas. You could also serve it with a side salad or another green vegetable such as broccoli or kale or you can eat it alone. Fish pie is particularly enjoyable with a glass of chilled white wine.


How long does Easy Creamy Fish Pie with Spinach keep for in the fridge?

You can store it in the fridge for up to 24 hours and enjoy any leftovers the next day. Make sure you leave it to cool and cover it before placing it in the fridge. Because this fish pie contains prawns I do not recommend leaving it for any longer than this. If you want to store leftovers for longer it's best to freeze them.

Can you freeze fish pie?

Yes this fish pie is a great dish for batch cooking as it can be frozen for up to 3 months. Just place it in an airtight container and put it in the freezer once it has cooled. You can reheat from frozen or defrost first. Reheat in the oven for the best results, but you can also microwave it if you are in a rush.

If you are making a fish pie with the intention of freezing it I recommend skipping the baking step and freezing the assembled fish pie once it has cooled. This way you will get a freshly cooked grilled cheese topping when you come to eat it.

fish pie in containers ready to be frozen
Why is my fish pie watery?

In this recipe the fish is cooked first to ensure it is fully cooked and does not add any excess water to the sauce. Spinach can also add extra moisture to the sauce. I recommend draining it with a colander and squeezing out any additional moisture before you add it to the sauce.

More easy fish recipes:

Easy Creamy Fish Pie With Spinach
Recipe details
  • 6  servings
  • Prep time: 20 Minutes Cook time: 30 Minutes Total time: 50 min
Show Nutrition Info
Hide Nutrition Info
Mashed potato topping:
  • 750g (or 26oz) Maris Piper potatoes or similar - peeled and chopped into even-sized (roughly 4cm or 1.5 inch) pieces
  • 2 tbsp butter
  • 80ml (or 3oz or ⅓ cup) milk
  • ½ tsp black pepper
  • Sea or kosher salt to taste
Fish pie filling:
  • 250g (or 9oz) spinach - washed
  • 1 tbsp oil
  • 200g (or 7oz) skinless cod or similar - cut into bite-sized pieces
  • 200g (or 7oz) skinless smoked haddock - cut into bite-sized pieces (note 1 & 2)
  • 200g (or 7oz) raw or cooked king prawns - butterflied and deveined if using raw
  • 4 tbsp butter
  • 4 tbsp plain flour
  • 200ml (7 fl.oz or ¾ cup) milk
  • 200ml (7 fl.oz or ¾ cup) fish stock
  • 1 clove of garlic - peeled
  • ½ tsp ground nutmeg
  • ½ lemon juice + zest
  • 2 tbsp fresh chives - finely chopped
  • 2 tbsp fresh dill - finely chopped
  • ½ tsp freshly ground black pepper
Other topping ingredients:
  • 75g (or 2.5 oz or ⅔ cup) grated cheese - either a mixture of cheddar and parmesan or just cheddar
  • A handful of dried breadcrumbs - optional

Heat your oven to 180°C or 350°F.
Place a saucepan of generously salted water on a high heat until it boils. Reduce to simmer, add the potatoes and cook for 15 to 20 minutes until you can easily place a fork through them. (note 3)
Meanwhile, place a large frying pan on a medium heat and cook the spinach until wilted. You may need to do this in two batches.
Place the spinach into a colander once it has wilted, drain the excess moisture by gently squeezing it with your hands and set it aside.
Wipe the frying pan you used to wilt the spinach clean and place it on a medium heat. Add oil and fry the cod and haddock for a few minutes until it is cooked and set it aside. (note 4)
Add the prawns and fry for 1-2 minutes until opaque. Add a little more oil to the pan if necessary. Set them aside with the cod and haddock when they are done.
Wipe the pan clean again and place it on a medium heat. Melt the butter, then stir in the flour and add the milk gradually and stir continually until a thick and creamy sauce is formed.
Stir in the fish stock and add the garlic clove, nutmeg, lemon juice and zest, chives, dill and a little black pepper to taste (I normally add ¼ - ½ tsp).
Stir the cooked fish, prawns and spinach and leave the sauce on your stove's lowest heat while you prepare the remainder of the fish pie.
When the potatoes are cooked, drain them using a colander and return them to the pan.
Add the butter and milk and mash until the potatoes are smooth and fluffy. Add extra milk if necessary. Season with black pepper and salt to taste.(note 5)
Remove the garlic clove and spoon the sauce into the baking dish.
Spoon the mashed potato onto the top and sprinkle with grated cheese and breadcrumbs (if using).
Grind a little fresh black pepper on top (no more than ¼ tsp) and bake in the oven for approximately 15 minutes until you see the sauce start to bubble around the edges of the mash potato topping and the cheese is melted and golden.
Place the fish pie under the grill for a few minutes to get the topping extra brown and crispy if desired.
  • If your fish has skin I recommend frying it whole and removing the skin before you cut it into bite-size pieces.
  • If you are using frozen fish make sure you fully defrost it first and remove any excess moisture with kitchen paper before frying.
  • I recommend setting a timer at this point so you do not forget about the potatoes while you prep the other ingredients.
  • The fish pieces are cooked when they are opaque. If in doubt, cut one of the larger pieces of fish in half to check the flesh is opaque all the way through.
  • The amount of salt you will need to add will depend on how the saltiness of the water you boiled the potatoes in. You shouldn't need more than ½ tsp.
Helen | Knife & Soul
Want more details about this and other recipes? Check out more here!