Wash and sort the mussels and remove the beard (see recipe: mussels in white wine stock). Select the sprouts, rinse and drain well. Clean, wash and cut the peppers into strips.
Clean, wash and cut the spring onions into rings. Remove the outer leaves from the lemon grass, chop the softer inside very finely. Clean the chilli, cut lengthwise, remove seeds, wash and chop finely.
Heat the oil in a large pot. Briefly fry lemon grass, chilli and curry paste in it. Add mussels, pour on coconut milk. Cover and cook. Meanwhile, wash the coriander, shake dry and remove the leaves.
Lift out the shells. Season mussel and coconut stock with soy sauce and lime juice. Simmer the peppers for about 5 minutes. In the meantime, remove part or all of the mussel flesh from the shells as desired.
Warm the sprouts, spring onions and mussels in the soup for about 1 minute. Season to taste again. Sprinkle with coriander and serve.