1 medium onion, peeled and finely chopped
100g piece of rindless streaky bacon, cut into rough 1cm pieces
1 tbsp plain flour
½ glass of dry white wine
1 litre fish stock
2 celery sticks, cut into rough 1cm pieces
salt and freshly ground white pepper
1 leek, cut into rough 1cm pieces, washed
300g waxy potatoes, peeled and cut into rough 1cm cubes
100ml double cream
2 tbsp chopped parsley
12 large oysters, shucked, juices reserved
Melt the butter in a large saucepan and gently cook the onion and bacon for 3–4 minutes without colouring until soft, stirring every so often. Stir in the flour and cook over a low heat for 30 seconds, then stir in the wine.
Gradually stir in the fish stock to avoid lumps forming, then bring to the boil. Add the celery and season with salt and pepper. Lower the heat and simmer for 20 minutes.
Add the leek and potatoes and simmer for a further 8–10 minutes or until the potatoes are tender. Ladle one-fifth of the soup into a blender and purée until smooth, then stir back into the soup.
Add the cream, chopped parsley and oysters together with any juices, re-season if necessary and simmer for another 2–3 minutes before serving.