This section is from the book "Economical Cookery", by Marion Harris Neil. Also available from Amazon: Economical Cookery (1918).
1 pinch salt
Buy the best steak. Take a sharp pointed knife, and holding it closely by the pointed end, shred meat fine, and mix it with an equal quantity of cold water in an earthenware jar or dish. Heat of any kind coagulates the juices, and if possible the water should be soft as well as cold. Add salt, which will help in extracting the juices more quickly from the meat. Cover jar, and set away in a cool place overnight.
Place jar at bottom of moderately hot oven, where it must remain from one to three hours, according to amount. Two cups of beef tea usually take two hours to cook slowly through. The oven should remain at the same temperature throughout the cooking. The best test is by the color of tea when removed from oven. It should be of a rich, brown color, with no red or raw traces. The substance is usually strained from the liquor, though in cases where an invalid is able and allowed to digest it, a portion of the meat particles may be permitted to pass through. Some substance will always pass through even the finest strainer, but if the beef tea be cooked satisfactorily, this substance should not easily separate nor sink to bottom of cup.
All suspicion of fat globules must be removed from surface with pieces of grease-proof paper, and if the tea appears to be greasy even after this application, it will be found safer to leave it to get cold, and then remove all fat after it has solidified. Serve tea piping hot with dry toast cut in dice.