Rinse the mushrooms well in a sieve under cold running water and soak them in the sherry for 1 hour, stirring occasionally.
Melt the butter in a saucepan and add the onions and cook covered over low heat until they are tender and lightly coloured – about 15 minutes, stirring occasionally.
Wipe the fresh mushrooms with a damp cloth and slice thinly. Add to the soup pot, season to taste with salt and pepper, and cook over low heat, uncovered, for 15 minutes, stirring frequently.
Carefully lift the dried mushrooms from bowl with a slotted spoon and transfer to soup pot. Pour the sherry into the saucepan, leaving the sediment behind.
Add the chicken stock and bring to the boil. Reduce heat, cover and simmer for 45 minutes or until dried mushrooms are tender.
Cool and purée soup, correct seasoning and thin soup with cream (if desired). Reheat and serve with crusty bread.
Recipes and styling: Taryne Jakobi
Photography: Vanessa Lewis