This section is from the book "The Boston Cooking-School Cook Book", by Fannie Merritt Farmer. Also available from Amazon: Original 1896 Boston Cooking-School Cook Book.
2 tablespoons butter 1/2 slice onion
3 tablespoons flour
1 cup Brown Stock 1/4 teaspoon salt 1/8 teaspoon pepper
Cook onion in butter until slightly browned; remove onion and stir butter constantly until well browned; add flour mixed with seasonings, and brown the butter and flour; then add stock gradually, bring to the boiling-point, and let boil two minutes.
1/4 cup butter 1 slice carrot 1 slice onion Bit of bay leaf Sprig of thyme
Sprig of parsley 6 peppercorns 5 tablespoons flour 2 cups Brown Stock Salt and pepper
Cook butter with carrot, onion, bay leaf, thyme, parsley, and peppercorns, until brown, stirring constantly, care being taken that butter is not allowed to burn; add flour, and when well browned, add stock gradually. Bring to boiling-point, strain, and season with salt and pepper.
To one cup Brown Sauce add one-fourth can mushrooms, drained, rinsed, and cut in quarters or slices.
1 can mushrooms
14 cup butter
1/2 tablespoon lemon juice
1/4 cup flour
2 cups Consomme or Brown Stock
Salt and pepper
Drain and rinse mushrooms and chop finely one-half of same. Cook five minutes with butter and lemon juice; drain; brown the butter, add flour, and when well-browned, add gradually Consomme. Cook fifteen minutes, skim, add remaining mushrooms cut in quarters or slices, and cook two minutes. Season with salt and pepper. Use fresh mushrooms in place of canned ones when possible.
 
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