Rehydrate the dried mushrooms in hot water for 30 to 45 minutes. Drain and slice.
Trim all fat off oxtails. Arrange in a shallow roasting tin. Roast in reheated oven for 45 minutes. Drain off any cooking fat, reserving about 2 tablespoons.
Add 250ml of water to roasting pan in which oxtails were browned. Heat, stirring constantly, to dissolve browned bits and make a gravy; reserve for later.
In a large stock pot, cook onion, carrots, parsnip, mushrooms and turnip in reserved cooking fat until soft, about 10 minutes. Add roasted oxtails. Drizzle brandy over the meat; ignite to burn off alcohol.
Pour gravy over the oxtails and vegetables. Add 1.25 litres of water. Add savory, bay leaf, barley, salt and pepper. Bring to the boil; reduce heat and cover. Simmer slowly for 2 hours. Adjust seasoning before serving.