Flour fry in a little sunflower oil. Diluted with cold broth while stirring, as the court is shifted from the heat until well have broken the mixture. Place the fire and diluted with the remaining broth while stirring to obtain the desired density. Separately, sauté the mushrooms. Add processed cheese and stir until the feta cheese is melted. The mixture was then poured into the flour sauce. Add egg yolks beaten with the juice of half a lemon, as boil for another 1-2 minutes stirring constantly. Add salt to taste and taste with pepper.