Sprinkle with trout fillet with lemon juice, put in a pot, add water, wine, onion and soup greens, parsley, bay leaf, peppercorns and 0.5 teaspoon salt. Bring to a boil, cook for 40 minutes. Strain the broth through a sieve, mix with cream, bring to a boil and evaporate half. Melt in a pan 20 grams of butter and fry the mushrooms with crushed garlic to the evaporation of all liquid. Cut the fish into small pieces, breaded in flour and fry in remaining butter for 5 minutes until golden brown, add the broth with cream and mushrooms, season with salt, mustard powder, bring to a boil and cook for 5 minutes on low heat. Rub the egg yolk and cream with vinegar and put in fricassee. Before serving, sprinkle with basil.