Blanch and trim sweetbreads. Boil water with vegetables and seasonings for 15 minutes, then add the blanched sweetbreads. Simmer for about 15 minutes.
Drain and cool. Normally, in French cooking the cooled sweetbreads would be placed between two plates, weighted down and refrigerated. I find wrapping them tightly in foil or transparent wrap an easier method of pressing them tight. Once cold and firm the sweetbreads are ready to slice and broil or sauté. Cook according to one of the following recipes.