Sufficient vinegar to cover the mushrooms; to each quart of mushrooms two blades pounded mace, one ounce ground pepper, salt to taste. Choose some nice young button mushrooms for pickling and rub off the skin with a piece of flannel and salt, and cut off the stalks; if very large, take out the red inside, and reject the black ones, as they are too old. Put them in a stewpan, sprinkle salt over them, with pounded mace and pepper in the above proportion; shake them well over a clear fire until the liquor flows and keep them there until it is all dried up again; then add as much vinegar as will cover them; just let it simmer for one minute and store it away in stone jars for use. When cold tie down with bladder and keep in a dry place; they will remain good for a length of time, and are generally considered excellent for flavoring stews and other dishes.
Source:
The Whitehouse Cookbook (1887)
