/Extra Crispy Fish Pie

Extra Crispy Fish Pie

Why have one recipe for Fish Pie when you can have two?

In fairness I was planning on making “Scott’s Fish Pie” – recipe here – until I saw a fish pie online that used grated potato (like a Rosti) for the topping instead of the mashed potato that I was planning to use. There are lots of variants of rosti that you could use from the dry and matchstick like through to the softer crisp-edged variety. Mine is more like the latter with a little basic seasoning rather than a long list of ingredients – but when you have such a good pie underneath you don’t need to make the top too complex. 

It looks good, it tastes good and it has a wonderful crunch in most mouthfuls. Add in the fact that it requires almost no effort what more could you want on a Monday night?

Extra Crispy Fish Pie

Sometimes it's nice to play with your food (when cooking it not eating it, mind you!) so when I saw a recipe that replaced the usual mashed potato on a fish pie with something more like a potato rosti I had to give it a go... This gives an amazingly crisp topping with a beautifully smooth pie underneath. Delicious!
Course Main Course
Cuisine Fish & Seafood
Prep Time 30 minutes
Cook Time 40 minutes
Total Time 1 hour 10 minutes
Servings 2
Author scottsilverthorn


Potato Topping

  • 500 g Potatoes
  • 20 g Butter, melted
  • 30 g Cheddar Cheese, grated

Fish Pie Mix

  • 400 g Mixed Fish of your choice - see note below
  • 90 g Prawns
  • 50 g Butter
  • 50 g Plain Flour
  • 1 tsp Dijon Mustard
  • 400 ml Semi-skimmed Milk
  • 30 g Cheddar Cheese, grated


Quick Note

  1. When it comes to the choice of fish in this sort of pie it really is up to you. The only thing I would say is to include a bit of something smoked as that certainly helps the overall flavour. As I often only cook for 2 people it's not always the sensible option to buy various fillets of fish separately, so I tend to pick up a "Fish Pie Mix" pack from the supermarket. This is generally a combination of White Fish (Cod, Haddock, etc), Salmon and Smoked Haddock, which does provide a great combination of flavours. If I have them to hand I'll also sneak in some prawns for a bit more texture and flavour, but like all of the fish in the pie they're entirely optional and you're in control.


  1. Preheat your oven to 190°C or equivalent if you're planning on serving the pies straight away. Otherwise you can assemble them earlier in the day and keep them in the fridge until needed, adding 5 minutes to the cooking time accordingly.
  2. Start by preparing the potatoes. Leave the skins on, but cut the larger potatoes in half so that you have everything about the same size. Add to a pan of salted, boiling water, bring back to the boil and cook for 7-10 minutes. You want them to be tender but still firm enough to grate. Drain and leave to one side to cool.
  3. Meanwhile make a light cheese sauce. Melt the butter in a pan over a medium heat. Add the flour to the melted butter and stir until the mixture comes together. 'Cook out' the flour for a minute or so.
  4. From here you start to slowly add the milk in stages and stir the mixture until it's all incorporated into the mix. I reckon 50-100ml a time should be plenty for each stage - it won't look pretty at first but it will quickly come together. A lot of people like to have the milk warmed before doing this but I just make sure it's at room temperature as it saves on washing up.
  5. Continue stirring over the medium heat until the sauce starts to thicken - don't take your eye off the ball at this stage or it may start to stick to the pan. This stage should leave you with a lovely thick, smooth sauce just before the sauce reaches boiling. Stir in the teaspoon of Dijon mustard at this stage.
  6. Grate the cheese into the sauce once you're happy with the consistency and take the pan off of the heat. Allow the sauce to cool down before using it
  7. From here it's just a case of assembling the ingredients into a delicious pie! If your fish isn't already in chunks then cut it into bite sized pieces and mix them into an oven-proof dish. I like to make individual pies so split the fish between two little pie dishes.
  8. Smother the fish with the sauce and then stir gently to ensure everything is well coated.
  9. Meanwhile grate the part-cooked potatoes into a separate bowl, then add in the melted butter and season well with salt and freshly ground black pepper. Stir gently to ensure the potato strands are well coated, then spoon over the top of the fish mixture.
  10. Put into the oven for 35-40 minutes, until crispy, golden and bubbling, adding the remaining grated cheese after about 15 minutes. When cooked through remove from the oven and allow to rest for 5 minutes before serving.