This recipe for seafood with cream and cheese from France can be found in Rick Stein’s “Seafood Odyssey”.
Peel the prawns, reserving heads and shells. Fry the onion in 15g of the butter until soft, then add the prawn heads and shells and cognac and fry for 1-2 minutes. Add the fish stock, wine and tomatoes, bring to the boil and simmer for 20 minutes.
Add the mussels to the pan and cover and cook over a high heat for 3-4 minutes. Strain through a large sieve set over a bowl. If there is less than 1 pint of stock make it up with a little fish stock. If there is more boil until reduced to the required amount.
Remove the mussels from their shells, discarding any that have not opened, and set aside with the peeled prawns. Discard everything else in the sieve.
Fry the shallots in another 25g of the butter until soft. Add the flour and cook for 1 minute, stirring. Gradually stir in the stock and bring to the boil, stirring. Add the cream and simmer very gently for 10 minutes, until the sauce coats the back of a wooden spoon. Add the parsley and season with lemon juice, salt and pepper.
Preheat the grill to high. Melt the remaining butter. Scatter the scallops, haddock and mushrooms into a large baking dish and brush with the melted butter. Season and grill for 2 minutes, then turn the scallops and grill for 2 minutes more.
Add the prawns, mussels and crab meat to the dish and spoon over the sauce. Sprinkle with the cheese, dust with paprika and cayenne and grill for another 1-2 minutes until golden and bubbling.