Preheat oven to 180 ºC.
Place duck legs in a roasting dish.
Mix together oil, fish sauce, lime juice and curry paste.
Rub mixture all over duck pieces and pierce skin with a fork.
Roast for 20 minutes, or until golden brown and crispy.
Place granadilla pulp, orange juice, sherry (or Contreau) and maple syrup in a saucepan and bring to the boil.
Mix cornflour and water into a paste, add this to the granadilla sauce and whisk until sauce thickens slightly.
Slice duck into portions and serve with granadilla sauce, coriander and fresh lime wedges.