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
Oyster ragout. Scald them, wash them well, and fry them in oil. Take browned bread, puree of peas or some of the water in which the oysters were scalded (or other hot boiled water), and wine (mostly), and sieve. Take cassia, ginger, cloves, grains_of_paradise and saffron (for colouring), steeped in vinegar. Add onions fried in oil, and boil together. It should be very thick. Some do not boil the oysters.