Heat the oil in a large frying pan, add the onion and cook for 5 minutes. Stir in the rendang paste, butternut squash and aubergine, and cook for a further 10 minutes.
Pour over the stock, bring to the boil and simmer for 20 minutes, adding the lamb and sugar snaps for the last 5 minutes. Stir through the yogurt and coriander and serve with the warm naan bread.