* 500 g (1 lb) smoked fish fillets, such as haddock
* 625 ml (20 fl oz / 2 1/2 cups) milk
* 4 carrots, cut into small dice
* 4 sticks celery, cut into small dice
* 90 g (3 oz / 1/2 cup) butter
* 6 sheets lasagne verde
* 3 teaspoons chopped fresh parsley
* salt and pepper
* 60 g (2 oz / 1/2 cup) plain flour
* freshly grated nutmeg
* 30 g (1 oz/6 teaspoons) grated Parmesan cheese
* lime twist and sprig of parsley, to garnish
1. Put fish and milk into a large sauce-pan. Bring to the boil, then simmer gently until fish is cooked.
2. Put carrots and celery into a saucepan with 30 g (1 oz/6 teaspoons) butter and 500 ml (16 fl oz/2 cups) water. Bring to the boil, then simmer until vegetables are tender. Meanwhile, in a large pan of boiling salted water, cook lasagne until just tender. Drain and spread out on a tea towel. Drain fish, reserving cooking liquid, and flake into a bowl. Drain vegetables, reserving liquid, and add to fish with parsley. Season with salt and pepper. 3. Preheat oven to 190C (375F/Gas 5). Make a Bechamel sauce with remaining butter, flour, vegetable water and milk from fish. Season with salt, pepper and nutmeg. Arrange a layer of lasagne in the base of an ovenproof dish. Cover with one-third of fish mixture then one-third of sauce. Repeat layers twice, ending with sauce. Sprinkle with Parmesan cheese. Bake in the oven for 25 minutes. Serve, garnished with lime twist and parsley.