Heat oil in a large pot.
Add ginger and onion.
Cook, stirring frequently for about 3 minutes.
Add broth and red pepper flakes and bring to a low boil.
Add cabbage and cook for approximately 2 to 3 minutes.
Add shrimp, lime zest and lime juice.
Cook just until shrimp turns pink.
Serve hot sprinkled with cilantro or scallions.