- one small spoonful of mustard made after the Dijon fashion;

- one small spoonful of the juice of a lemon, newly pressed;

- half a small spoonful of clean coarse salt;

- half a small spoonful of sharp white-wine vinegar of Champagne;

- the fourth part of a small spoonful of dried onion, beaten to a fine powder; and

- the like quantity of dried garlic, likewise powdered.

With a small whisk, molinet, or stout wooden spoon, beat all together without ceasing. Then let fall, by a slender thread, one gill and a half of oil pressed from the avocado pear, still beating it lustily, until the sauce be grown pale, smooth, and thick enough to stand upon the spoon.

Keep it in a cool place, well covered, and spend it whilst it is fresh.

(https://autoadmit.com/thread.php?thread_id=5896985&forum_id=2#50091488)