Serves 8 1 bunch of fresh flat-leaf parsley 1.2 litres whole milk 1/4 of a medium onion, peeled 1 fresh bay leaf 4 black peppercorns 320g frozen white fish fillets 320g frozen salmon fillets 80g unsalted butter 80g plain flour Zest and juice from 1 unwaxed lemon 300g frozen peeled cooked prawns 300g frozen peas Sea salt and freshly ground black pepper Basic mash made with 3kg Maris Piper or King Edward potatoes Preheat the oven to 220C/425F/gas 7. Pick the parsley leaves and set aside for later, then tie the stalks together with string and place in a large pan over a medium heat with the milk, onion, bay leaf, peppercorns and fish fillets. Simmer gently for about 15 minutes, or until the fish is cooked through.

Using a slotted spoon, remove the fish to a plate and leave to cool. Carefully strain the milk through a sieve into another pan and put to one side.

Melt the butter in a pan over a medium heat, then whisk in the flour, until well combined.

Gradually add the warm milk a splash at a time, whisking continuously until any lumps have disappeared and you have a smooth white sauce – you may not need to add all the milk, so use your brain and stop when it’s looking good.

Add the lemon zest and juice, then roughly chop and add the parsley leaves, stir in the prawns and peas and add a pinch of salt and pepper.

Flake the fish into a 25cm x 30cm baking dish, spoon over the sauce and top with my basic mash. Roughly smooth it out to the edges, then use a spoon to scuff it up.

Bake in the oven for about 25 minutes, or until golden and bubbling at the edges. Serve with steamed broccoli or a crisp green salad.

Recipe from The Family Cook Book by Kerryann Dunlop