The basis of this soup is a good fish stock which can easily be made using the slightly salted water that lobster or crab has been boiled in along with any shells and legs and a few lemon slices.
In a heavy saucepan, cook the onions and garlic in the butter until soft. Cut the fish into smallish pieces and add, with the shellfish, to the pan. Let this simmer, but not brown, add the tomato purée, tinned tomatoes, potatoes, cayenne, bouquet garni, some lemon juice and the wine. Stir together gently and season to taste with salt and pepper, and more lemon juice if necessary. Add the fish stock, heat through, taste again and serve.
© 1988 Keith Floyd estate. All rights reserved.