Make the curry paste, by blending until smooth. Then add to a large pan or wok and fry off with oil.
Add in the cubes of tofu, then pour in coconut milk. Stir well then bring up to the boil. Pop in sugar and soy sauce.
Add in roasted sweet potato and stir well. Make sure the sweet potato is heated through.
Wilt in the spring greens for a few minutes, until piping hot. Serve over cooked rice noodles and top with fried shallots and chilli flakes.