1.First heat the oven to 200°C. To cook fish stock, skin the fish fillets and place the skin in a large stockpot with the fish bones, thyme, bay leaf, peppercorns and lemon slice. Add the water&wine and boil it.Simmer for 20 minutes.
2. Cut wax paper or baking parchment into large ovals big enough to form a parcel for each
fish fillet. Fold the paper in half and lightly oil both sides.
3.Place the fish fillets on one half of the paper and arrange the prawn and crab claws on top of each fillet.
4.Melt the butter in a pan and while foaming, add the flour. Cook at a medium heat for 2-3 minutes, stir repeatedly until it turns in to pale straw color with onions
5.Gradually pour on the fish stock, whisking continuously. Cook over moderate heat for about 4-5
minutes, or until the sauce thickens.
6.Mix the egg yolks with a few spoonfuls of the hot sauce and then stir the egg yolks into the sauce. Spoon some of the sauce over each fillet and seal the parcels, folding the edge over twice and twisting the ends slightly to seal completely.
7.Place the
parcels on baking sheets or in shallow baking pans and place in the preheated oven for about 20 minutes.