Adapted from a BBC Food recipe. 

Mashed potatoes with a bit of butter, milk and crème fraiche. 

500ml/1 pint milk

250g/9oz smoked haddock

200g/7oz cod loin

1 onion

1 bay leaf

3 cloves

2 leeks, washed and chopped

50g butter

1 tbsp olive oil

3 tbsp flour

salt and white pepper

100g raw king prawns

50g  frozen peas

Frozen chopped spinach

1 tbsp finely chopped parsley

Grated cheese

1 lemon, zest only

Preheat the oven to 190C/375F/Gas 5.

Make mashed potato. 

Heat the milk in a large pan, add the fish with half an onion in half, bay leaf and cloves.  Bring the milk up to the boil and simmer gently for 6-7 minutes.

Meanwhile, fry the remaining half onion and the leeks in the butter and olive oil in a separate pan until soft but not brown. 

Remove the fish from the milk, break into flakes and set aside. Keep the milk in the pan.

Add the flour to the leeks and stir well to make a roux. Add the poaching milk to make a white sauce. 

Fold the fish pieces, prawns, peas, spinach and chopped parsley into the sauce.

Spoon the fish mixture into the bottom of the ovenproof dish. Sprinkle fresh chopped parsley and grated lemon zest over the top.

Carefully top with the cooled mashed potato and cheese. 

Place in the oven for 25-30 minutes, or until golden-brown and bubbling.