Equipment
* optional
Ingredients
Cheddar Mashed Potato
- 1000 g floury potatoes, peeled and cut into even chunks
- 50 g unsalted butter, cubed
- 50 ml whole milk, warmed
- 120 g mature cheddar cheese, grated
- fine sea salt
Seafood Base
- 300 g skinless boneless cod fillet, cut into 3cm chunks
- 300 g smoked haddock, cut into 3cm chunks
- 150 g raw king prawns, peeled and deveined
Leek and Cream Sauce
- 50 g unsalted butter
- 150 g leek, cleaned, trimmed, and finely sliced
- 40 g plain flour
- 50 ml dry white wine
- 150 ml fish stock, warm
- 300 ml whole milk, warm
- 50 ml double cream
- 10 g dijon mustard
- 100 g frozen garden peas
- 5 g fresh dill, finely chopped
- 1 lemon, zested
Nutrition (per serving)
Nutrition is estimated per serving. Nutrients without complete source data are omitted.
Full nutrition
- Calories
- 550 kcal
- Protein
- 41 g
- Carbohydrates
- 37 g
- Fat
- 27 g
- Fiber
- 6 g
- Sugar
- 6 g
- Sodium
- 708 mg
- Saturated Fat
- 16 g
- Trans Fat
- 0 g
- Monounsaturated Fat
- 5 g
- Polyunsaturated Fat
- 1 g
- Cholesterol
- 152 mg
- Potassium
- 1422 mg
- Calcium
- 345 mg
- Iron
- 7.8 mg
- Magnesium
- 120 mg
- Phosphorus
- 549 mg
- Zinc
- 2.6 mg
- Vitamin A
- 288 mcg
- Vitamin C
- 34 mg
- Vitamin D
- 1.7 mcg
- Vitamin E
- 1.4 mg
- Vitamin K
- 18 mcg
- Vitamin B6
- 0.8 mg
- Vitamin B12
- 1.7 mcg
- Thiamin
- 0.26 mg
- Riboflavin
- 0.34 mg
- Niacin
- 6.5 mg
- Folate
- 84 mcg
- Water
- 375 g
- Alcohol
- 1 g
Sources: Aggregated Public Data, USDA FoodData Central
Method
Preheat the oven to 200°C/400°F and generously butter a 2-liter baking dish.
Place the potatoes in a large saucepan of heavily salted cold water. Bring to a boil, then reduce heat and simmer until completely tender, about 15-20 minutes.
Drain the potatoes thoroughly and let them steam dry in the colander for 2 minutes to remove excess moisture. Pass them through a potato ricer back into the saucepan, or mash thoroughly.
Mix the butter, warm milk, and grated cheddar cheese into the hot mashed potatoes. Season with salt to taste. Cover to keep warm.
Melt the butter for the sauce in a medium saucepan over medium heat. Add the sliced leeks and cook gently until softened but not browned.
Sprinkle the flour over the softened leeks and stir well. Cook for 1-2 minutes to cook out the raw flour taste, creating a blonde roux.
Pour in the white wine and whisk vigorously to combine. Gradually pour in the warm milk and fish stock, whisking continuously to prevent lumps from forming.
Bring the sauce to a gentle simmer and cook until nicely thickened. It should easily coat the back of a spoon.
Remove the sauce from the heat. Fold in the double cream, Dijon mustard, frozen peas, chopped dill, and lemon zest. Taste and adjust seasoning.
Pat the raw cod, smoked haddock, and prawns completely dry with paper towels. Scatter the seafood evenly across the bottom of the prepared baking dish.
Pour the warm cream and leek sauce evenly over the raw seafood, ensuring everything is well coated.
Spoon or pipe the warm mashed potato evenly over the top of the filling, sealing it to the edges of the dish. Rough up the surface with a fork to create peaks that will crisp in the oven.
Bake in the preheated 200°C/400°F oven until the potato topping is golden brown and the filling is fiercely bubbling around the edges.
Remove the pie from the oven and allow it to rest before serving to let the sauce settle and prevent burning mouths.
Chef's Notes
- Scoring the top of the mashed potato with a fork creates ridges that catch the heat and crisp up beautifully. For a professional finish, you can pipe the potato using a star nozzle.
- Undyed smoked haddock provides an authentic, delicate smokiness without the artificial yellow coloring commonly found in commercial smoked fish.
- Do not pre-cook the fish; allowing it to gently poach in the sauce while baking prevents it from overcooking and becoming rubbery.
- To prevent a watery sauce, ensure you pat the seafood completely dry before placing it in the dish.
- Letting the potatoes steam dry after boiling is crucial. Waterlogged potatoes will make your mash thin and prevent it from holding its structure on top of the pie.
Storage
Refrigerator: 3 days — Store in an airtight container. The sauce may thicken slightly upon chilling.
Freezer: 2 months — Freeze before baking for best results. Thaw overnight in the refrigerator before baking.
Reheating: Reheat portions in the oven at 180C until piping hot to maintain the crisp potato crust. Microwaving is faster but softens the topping.
Troubleshooting
The sauce is too thin or watery after baking
Cause: The seafood released excess moisture into the sauce during baking
Fix: Allow the pie to rest for 15-20 minutes before serving so the starches can settle and thicken the liquid.
Prevention: Thoroughly pat the raw fish dry before assembling. Ensure the sauce base is reduced to a thick consistency before pouring it over.
The fish is rubbery and dry
Cause: Fish was pre-cooked before going into the oven
Fix: Cannot be fixed
Prevention: Always use raw fish in the assembly stage. It will poach perfectly in the sauce as the pie bakes.
Potato sinks into the sauce
Cause: Sauce was too thin or potato was applied when the sauce was too hot
Fix: Cosmetic only, will still taste excellent.
Prevention: Spoon the potato around the edges of the dish first, working your way into the center to create a structural bridge.
Cultural Context
Fish pie is a cornerstone of traditional British home cooking, originally devised to utilize offcuts from the daily catch. Unlike meat pies, it does not use a pastry crust, instead relying on the abundance of root vegetables in the UK to form a hearty, insulating lid.
