This section is from the book "Scientific Feeding", by Mrs. Dora C. C. L. Roper. Also available from Amazon: Scientific feeding.
Soups prepared from legumes, fruits or cereals require an addition of fat in the form of butter, oil, the yolk of an egg, cream, or fat meat.
A soup of peas, beans, corn or lentils may be prepared from left-over food or fresh cooked legumes. To one cup of cooked legumes add three to five cups of hot water or weak soup stock, boil or mix well, then strain. Heat one or two tablespoonsful of butter or half butter and half cooking oil, add to this one or two tablespoonsful of mixed flour, let boil, then add the hot broth at short intervals, stirring to prevent lumps. When all the broth is used, let the whole boil a few minutes. Remove from the fire, flavor with lemon juice, pepper, bay leaves, chopped fresh thyme, sage or parsley, and serve.
To these soups an addition of hot cream may be made before serving, if desired. They form a perfect and an economical meal without the addition of meat, eggs, fish or other protein foods. Celery, lettuce, raw apples and crackers with butter are a good addition. They should be well masticated, and the soup eaten with them very slowly.
Wash 1 1/2 cup of black, white red or mixed beans and soak in 1 quart of warm soft water over night. The next day add about 5 pints of cold or boiling water to the beans, let come to a boil; add two finely cut onions and a potato, parsley or other flavoring. Then wash 1/2 pound of bacon several times with hot and cold water and put on to boil in sufficient water to cover it. Let boil 5 or 10 minutes, pour off the water and put the bacon into the bean soup. Let all boil for about an hour; when the meat is tender, take it out and put on a plate to cool. Let the soup simmer slowly for 3 hours or longer; then strain. Let stand a little while, remove the fat and mix it with 2 or 3 tablespoonsful of flour in a clean saucepan over the fire, add the strained bean soup gradually, let all boil a few minutes and serve. If the soup is desired thin, use only a part of the fat and a little flour. A cupful of strained tomato juice and chopped parsley may be added before serving. This should make five soup plates full. Serve with fried bread or bread and butter and raw carrots.
Prepare like the foregoing. Leave out the meat, butter, flour, and tomatoes; mix with one-fifth part or less of hot cream before serving. Add plenty of chopped parsley.
Prepare like bean soup. Flavor with celery roots or stems.
Strain a can of tomatoes and heat. Add an equal amount of boiling water or soup stock. Heat some oil, butter or fat; add flour, boil a few seconds; then add the tomato juice gradually and a little salt. Boil all 3 to 5 minutes, then serve. It must be of the consistency of gravy. Raw cucumbers and celery are a good addition.
Prepare like the foregoing. Add 1/4 part or more of hot cream before serving. If milk is used, it must be more in proportion than cream.
 
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