2 celery sticks, roughly chopped
1 small fennel bulb, roughly chopped
1.5kg/3lb 5oz floury potatoes (such as King Edward), peeled and cut into large chunks
1 small onion, roughly chopped
few sprigs fresh parsley
2 tbsp chopped fresh tarragon
40²µ/1½´Ç³ú plain flour
1 bay leaf
salt and black pepper
pinch of saffron
600ml/20fl oz fish stock
50g/1¾oz unsalted butter
40²µ/1½´Ç³ú unsalted butter
100ml/3½fl oz double cream
250g/9oz smoked langoustines
250g/9oz salmon fillet, skinned and boned
500g/1lb 2oz haddock fillet (or other white fish of your choice), skinned and boned
50ml/2fl oz anise-flavoured liqueur, such as Pernod