Black Pepper Sauce

The Viander of Taillevent (French, between 1380 - 1395)
"Poivre Noir. Black Pepper Sauce. Grind ginger, round pepper, and burnt toast, infuse this in vinegar [and a little verjuice], and boil."

Le Menagier de Paris (French, 1393)
"BLACK PEPPER. Take a clove and a little pepper, ginger, and grind very fine: then grind toasted bread soaked in a little liquid from the meat or in a little cabbage-water which is better, then boil in an iron pan, and when boiling add vinegar; then put in a pot on the fire to keep hot. Item, some add cinnamon to it."

Ashmole 1439 (circa 1430-40)
"Take brede, and frye it in greece, draw up with brothe and vinegre; caste ther-to poudre piper, and salt, sette on the fire, boile it, and messe it forth."

The Cookbook of Sabrina Welserin (German, 1553)
"Make [the sauce] so: Take rye bread, cut off the hard crust and cut the bread into pieces, as thick as a finger and as long as the loaf of bread is. Brown it over the fire, until it begins to blacken on both sides. Put it right away into cold water. Do not allow it to remain long therein. After that put it into a kettle, pour into it the broth in which the game was boiled, strain it through a cloth, finely chop onions and bacon, let it cook together, do not put too little in the peppersauce, season it well, let it simmer and put vinegar into it, then you have a good peppersauce."