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Fish and seafood

Fish pie with celeriac mash

Robbie Puddick (RNutr)
Written by

Robbie Puddick (RNutr)

Content and SEO Lead

Dr Rachel Hall
Reviewed by

Dr Rachel Hall (MBCHB)

Principal Doctor

3 min read
Last updated October 2026
title

Prep and cooking time: 120 mins

  • Freezable
  • High-protein

Ingredients

Serves: 4

  • 2 celeriacs (approx 700g) or swede, diced
  • 500ml milk
  • 2 bay leaves
  • 1 small brown onion, quartered
  • 40g butter
  • 40g wholewheat flour
  • 240g smoked haddock, cut into 4cm pieces
  • 240g salmon fillets, cut into 4cm pieces
  • 250g cod, cut into 4cm pieces
  • 165g raw or frozen prawns, peeled
  • 1 small handful fresh parsley, finely chopped
  • 2 tbsp butter
  • 40g parmesan, grated
  • 200g green beans, sliced lengthways
  • 1 large broccoli, steamed
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Method

Step 1

Preheat the oven to 200°C/180°C fan.

Step 2

Add the diced celeriac or swede to a large saucepan with boiling water. Cook for roughly 30-40mins, or until soft. If using swede, boil for longer so it’s completely softened. Once cooked, squeeze out any excess water through a strainer.

Step 3

In a small saucepan, add the milk, bay leaves, onion, peppercorns, and salt. Bring the milk to a boil, and remove from heat. Strain out the bay leaves, onion, and peppercorns, and set aside.

Step 4

In a separate, medium-sized saucepan, add the butter, and melt. Add the flour, and continue to stir into the melted butter until thick paste forms. Continue stirring and cooking out the flour for 1.5-2mins.

Step 5

Slowly pour in the infused milk and whisk together with the flour paste. Cook until thick and coating the spoon.

Step 6

Once the creamy sauce is finished cooking, turn off the heat, add the fish and parsley, and set aside.

Step 7

Strain the cooked celeriac and place back into the saucepan you used to boil. Add the butter and parmesan, season with salt and pepper, and blend with a stick blender until smooth.

Step 8

Pour the creamy fish mixture into an ovenproof baking tray, cover with the mash, and cook in the oven for 45mins-1hr.

Step 9

Just before the fish pie finishes cooking, steam the vegetables and serve hot!

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