Sweetbread with Tomato Sauce

This is a cross-reference entry: Farmer expects you to have already read the sweetbread cutlet recipe a page or two earlier. The preparation it assumes is the part that actually matters, so here it is in full.

• What a sweetbread isA gland of a calf, sold in pairs joined by a tube: the round, plump "heart" sweetbread and the longer, flatter "throat" or neck sweetbread, the latter being the thymus proper. The round one is generally reckoned the prize. Sweetbreads usually have to be ordered ahead; about 1 lb is commonly reckoned enough for four.
• The step the recipe hidesSweetbreads must be soaked in several changes of cold water until no longer pink (an hour or two), then parboiled 15-20 minutes in acidulated salted water, then plunged into ice water. Only when cold can you peel the membrane and pull away the connective tissue without shredding the meat.
• Press before slicingAfter trimming, lay the sweetbreads flat between two plates with a weight on top and chill at least an hour. Unpressed sweetbreads are spongy and will not hold a neat cutlet shape or take a crumb coating evenly.
• Deep fatThe book gives no thermometer reading for "fry in deep fat"; the fat is judged by browning a cube of bread, about forty seconds for an already-cooked mixture (roughly 375F by modern reckoning). Egg-and-crumb the slices and fry two or three minutes to a deep gold; the parboil has taken them most of the way, so the frying is largely a matter of setting the crust.
• Sautéing insteadMedium-high heat, clarified butter or butter with a little oil so the milk solids do not burn, two to three minutes a side. Season after the crust forms.
• The tomato sauceFarmer's version is a butter-and-flour sauce thinned with stewed and strained tomatoes; the exact seasoning varies. Any sharp, smooth tomato sauce works; the point is acidity against a rich, faintly sweet organ meat.
• Buy them fresh and cook them fastSweetbreads are among the most perishable things in a butcher's case. Soak and parboil the day you buy them, and hold the blanched, pressed glands no more than a day in the refrigerator before finishing.