Heat oil in a large saucepan over high heat, add the lamb and brown in batches. Remove and set aside.
Reduce heat to medium, add onion, garlic and ginger to pan and cook, stirring, for 5-6 minutes. Add paste and cook, stirring, for 2-3 minutes.
Return lamb to pan, add stock and bring to the boil. Reduce heat and simmer for 30 minutes. Add the potato, carrot, peas and coconut milk and cook for a further 25 minutes.
Garnish with coriander and serve with rice.