This conserve of milk-cap mushrooms can also be made with other types of wild mushrooms (pine mushrooms, porcini, chanterelles, March mushrooms, etc.). It is best to use the smaller button-type mushrooms. They are ideal for an aperitif or for eating in salads. Some people add a bay leaf or a sprig of thyme.
Clean the milk cap mushrooms and cut off the end of the stalk. Wipe with a damp cloth to remove any impurities. Heat some oil in a casserole with the vinegar, the mushrooms, a pinch of salt, a few peppercorns, the peeled garlic, the thyme and the marjoram Bing to the boil and remove from heat. Place the mushrooms in wide-mouthed glass jars and fill with the cooking liquid. Cover the jars and place in a pan covered with cold water. Simmer the jars for twenty minutes once the water comes to the boil. Remove from heat and leave to cool. Dry the jars, label them and store in the larder for a few weeks.