Trout soup with sorrel

Preparation:

Preparation: Soak the trout trimmings in a bowl full of water. Melt the butter gently in a saucepan, add the finely chopped shallots and let it brown over moderate heat for 3-4 minutes, avoiding letting it brown. Add the trout trimmings, drained, and fry everything for a couple of minutes. Finally, pour the water and Riesling into the bowl, add the necessary salt and thyme and bring to the boil. Cook over low heat for 3-4 minutes, continuously eliminating the foam that forms on the surface of the liquid. After the indicated time, remove the heads from the broth, remove the pulp, which you will keep aside, and put them back in the saucepan. Continue cooking for another 15 minutes, then filter the fumet through a sieve covered with a cloth. Collect the liquid you obtain in a clean casserole and let it reduce until you get about 3/4 of a liter of fumet, then remove it from the heat and let it cool. Melt the butter in a saucepan, add the flour and fry over low heat, stirring constantly, without letting it brown. Wet the sautéed mixture with the cold trout fumet, bring to the boil, stirring with a whisk, and cook over moderate heat for 10 minutes. Beat the egg yolks with the cream and add the mixture obtained to the soup, which should no longer boil from now on. Filter the preparation through a sieve lined with a cloth, collecting the proceeds in a clean pot. Whip it with an immersion blender, finally season with salt and add the trout meat and the finely chopped sorrel. Finally add the sorrel and the pulp removed from the trout heads, then serve.