Veal Sweetbreads Sweated in Sauternes

• 2 lb veal sweetbreads
• finely chopped mirepoix, based on ¼ lb each of onions</

Whatever the final preparation, sweetbreads should first be soaked in cold water for several hours or overnight, with several changes of water or in an over-running basin fed by a trickling tap. Put into a large saucepan, cover abundantly with cold water and bring slowly to a near simmer. Hold over low heat, beneath the boil 180°-190°, for about 20 minutes, then drain and immerse in cold water.