Massaman duck curry

Ingredients

• 1 cinnamon stick
• 3 tbsp sunflower or groundnut oil
• 1 small aubergine, about 275g, cut into 2.5cm cubes
• 2 duck breasts, about 320g, skin removed
• 40g unsalted peanuts or cashew nuts, roughly chopped
• 4 shallots or 1 small onion, finely sliced
• 2 medium floury potatoes (about 350g), preferably Maris Pipers, peeled and cut into 2cm chunks
• 95g massaman curry paste (from a jar)
• 1 star anise

• 400ml light coconut milk 

• 1 tbsp Thai fish sauce
• 1 tbsp soft light brown sugar or palm sugar
• 100g green beans, trimmed and halved