Ingredients: White stock, eggs, butter, peas, white beans, carrot, onion, leeks, celery, cream croutons.
Soak one pound of white beans for twelve hours, then put them into a stock pot with a little salt, butter, and water, add a carrot, an onion, two leeks, and a stick of celery, and simmer until the vegetables are well cooked; then take out all the fresh vegetables, drain the beans and pass them through a sieve, but first dilute them with good stock. Put this puree into a stock pot with good white stock, and when it has boiled keep it hot in a bain-marie until you are about to serve; then mix the yolk of three eggs in a cup of cream, and add this to the soup. Pour the soup into a warm tureen, add some boiled green peas, and serve with fried croutons handed separately.
See also: Wikipedia Cookbook.
Source: ''The Cook's Decameron: A Study In Taste, Containing Over Two Hundred Recipes For Italian Dishes'' from a project that puts out-of-copyright texts into the public domain. This is from a *very* old source, and reflects the cooking at the turn of the last century. Update as necessary.