This section is from the book "A Handbook Of Invalid Cooking", by Mary A. Boland. Also available from Amazon: Handbook of Invalid Cooking.
Select fair, sound, tart apples. Wash and wipe them, and cut out the cores with an apple-corer, being careful to remove everything that is not clear pulp. Sometimes the tough husk which surrounds the seeds extends farther than the instrument will reach with once cutting; this can be detected by looking into the apple, and removing with the point of the corer anything that remains. If there are dark blotches or battered places on the outside of the apple, cut them off. Everything of that kind is valueless as food, and injures the flavor of that which is good.
When they are prepared place the apples in an earthen baking dish (granite-ware will do), put a teaspoon of sugar and half an inch of dried lemon-peel, or fresh peel cut very thin, into each hole, pour boiling water into the dish until it is an inch deep, and bake in a moderately hot oven; when the skins begin to shrink and the apples are perfectly soft all the way through, they are done; then take them from the oven, arrange them in a glass dish, and pour around them the syrupy juice that is left.
The time for baking varies, according to the species of apple, from half an hour to two hours. They should be basted once or twice during the time with the water which is around them. It will nearly all evaporate while they are baking. If the apples are Baldwins, or Greenings, or any others of fine flavor, the lemon-peel may be omitted. Stick cinnamon may be used instead of lemon-peel for apples which are not quite sour.
 
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