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
Yellow Pepper [Sauce]. Crush ginger, saffron and browned bread, steep in vinegar, and boil. Some cooks add grains_of_paradise, cloves and verjuice. (BN manuscript, p. 33.)
Other versions of this recipe:
YELLOW OR BITTER PEPPER (Le Menagier de Paris)
Yellow Sauce (Le Viandier de Taillevent)