This is an excerpt from Le Viandier de Taillevent
(France, ca. 1380 - James Prescott, trans.)
The original source can be found at
James Prescott's website
Mutton haricot. Take raw mutton, cut it into small pieces, and fry it lightly in lard with some finely chopped onions. Steep it in beef broth, add some wine, verjuice, mace, hyssop and sage, and boil well together.
Other versions of this recipe:
HARICOT of MUTTON (Le Menagier de Paris)