1 carrot, roughly chopped
1 onion, chopped
2 tbsp chopped flatleaf parsley
陆 a swede, roughly chopped
1 waxy potato, roughly chopped
1 tsp black mustard seeds
1 tbsp plain flour
8 peppercorns
1 tsp turmeric
25g/1oz butter
568ml/1 pint milk
2 haddock fillets