6ouncesfresh blewit or other mushroomspreferably buttons, cut into 1 inch pieces, left whole if small, or quartered. The best preserved mushrooms will be made from whole, small buttons.
1small shallothalved and sliced very thin
1teaspoonkosher salt
¼cupdry white wine
5cracks of the peppermillor 1/8 teaspoon fresh ground black pepper
½cupwalnut oil
1tablespooncooking oilfor sweating the mushrooms
2teaspoonschopped fresh sagethyme, or oregano
1/3cupapple cider or champagne vinegar
Instructions
Rinse the mushrooms with water to clean them, but also help add liquid to the preserving liquid.
In a pan with deep sides, sweat the mushrooms and shallots with the salt, pepper, sage, and the tablespoon of cooking oil until the mushrooms are soft, covered, about 5 minutes.
Be careful the mushrooms and shallots don’t brown, as you want them to stay blonde. Add the wine and simmer for a few minutes more to cook off the alcohol.
Finally add the vinegar and walnut oil, double check the seasoning by tasting a mushroom, then transfer to a container and refrigerate until needed.
Make sure the mushrooms always stay under a layer of liquid, otherwise they could go bad. The mushrooms will keep for a long time, but you should eat them in a month or two.
For long term preservation they could be canned, but the liquid must completely cover everything in the jar.