Heat the oil and fry the duck breasts until golden
brown. Add the spring onions, garlic and ginger and
fry for 2 minutes.
Add the soy sauce, wine or
sherry, sugar and salt and mix well. Add the water,
bring to the boil, cover and simmer for about 1 1/2
hours until the meat is very tender.
Mix the corn-flour with a little water then stir it into the
pan and simmer, stirring, until the sauce thickens.