1 (about 2.2kg) duck12green onions, trimmed10 cm piece ginger, thickly sliced2 pieces cassia bark60 ml (¼ cup) fish sauce5star anise1 cup (loosely packed) each coriander and mint leaves½ cup (loosely packed) Vietnamese mint leavesTo serve:lime wedges
Place duck in a large saucepan and cover with water, bring to the boil over medium heat, then drain, add 8 green onions, ginger and spices and cover with 4 litres of cold water. Bring to the boil over high heat, then reduce heat to low-medium and simmer for 3 hours. Add fish sauce and season to taste with sea salt and freshly ground white pepper.
Remove duck from liquid and place on a platter. Strain liquid and skim fat, then ladle broth among serving bowls. Coarsely shred duck meat and add to bowls. Thinly slice remaining green onions and divide among bowls, scatter with herbs and serve immediately.