Add the liquids, sugar, salt, and herbs to a saucepan. Dissolve the sugar, and bring to the boil. Skim off the herbs and peppercorns. Blanch the whole mushrooms in the boiling pickling juice. Allow the mushrooms and pickling juice to cool down separately. Once cool, cover the mushrooms with the pickling juice and store in jars.
Recipe courtesy of Christiaan Campbell of Delaire Graaff Estate Restaurant.