Usually considered a mayonnaise-based sauce invented by the French --…
From Liber de Arte Coquinaria — The Art of Cooking (1465) — an early Renaissance cook book compiled, written, and likely “plagiarized” by Martino da Como who lived 1430-1500 — here’s a recipe for white garlic sauce.
Da Como could be described as something of a celebrity chef and the book represents the culinary in transition from the Medieval to the Renaissance period. I love the casual “as you wish” instructions and the almost haphazard recording of the process.
Take some almonds that have been carefully peeled and crush; when they are half-crushed, add however much garlic you like, and crush together adding some cool water so that they do not purge their oil.
Then take some bread white and soak it in lean meat broth, or fish broth if on a fast day; and you can serve this garlic sauce to suit all seasons, fat and lean, as you wish.