Heat the oil in a wok over medium heat.
Add the garlic, spring onion and one of the chillies. Stir until lightly browned, then add the green curry paste.
Add all the vegetables and coat well in the paste. Don’t worry if the wok seems rather full, the vegetables will reduce in size significantly.
Pour in half of the coconut milk and add the kaffir lime leaves. Mix well.
Cover the wok with a lid for five to 10 minutes, lifting it to stir occasionally.
Remove the lid after 10 minutes, add the remaining coconut milk and spinach, then simmer for a further 15 minutes on low-medium heat, stirring occasionally.
Insert a knife into a sweet potato chunk to test if it’s soft. If it’s still a little hard, continue to simmer for five more minutes. Otherwise, stir through the lime juice, then remove the wok from the heat.
Garnish with coriander and the remaining chilli.
Serve with brown rice.