Nigel Slater's Leek and Mussels Chowder

Thinly chop 3 medium leeks and wash them very carefully. Cut 150 g of smoked bacon into thin strips and place them in a deep saucepan with 40 g of butter. Place over moderate heat and cook the bacon for a few minutes until the fat is golden brown. Lower the heat and add the leeks, then cover with a lid. Cook for about 20 minutes, until the leeks are soft and sweet. Check occasionally to ensure they don't stain.

Have 750g of mussels ready, washed and checked, discarding any cracked or broken shells or those that do not do not close instantly when tapped against the side of the sink. Put them in a large saucepan, pour 100 ml of white vermouth or white wine, then cover tightly with a lid and bring to a boil. Cook for a minute or two, then check their progress. If mussels are open, remove from heat. Otherwise, give them a minute or more.

Remove the mussels from their shells, reserving the cooking juices and discarding the shells. Sprinkle 2 tablespoons of flour over the leeks and continue cooking for 2 minutes, then pour the cooking juices from the mussels using a fine sieve to collect the shells and grains.

Pour in 250ml of fish or vegetable stock, bring to the boil, then stir 250ml of whipping cream into the pan and bring back to the boil, seasoning with salt (you may only need one little) and black pepper.

Chop a generous handful of parsley and stir in. Add mussels and pour into bowls. Enough for 4

You can add water instead of broth. There's plenty of flavor in the mussel cooking liquor already.

I sometimes make this a bit more substantial by toasting slices of baguette and putting them in the bowl before pouring over soup.

The Observer aims to publish seafood recipes rated as sustainable by Marine Conservation's Good Fish Guide Society

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