Heat the oil and fry the onions for 5 minutes. Add ginger and garlic and fry for another 2 minutes. Stir in the flour.
Immediately pour in the broth, coconut milk, corn and red bell pepper, salt and pepper to taste. Stir, bring to a boil and let it simmer for 15 minutes.
Puree the soup with the hand blender. Divide the soup over the bowls and sprinkle some green onions in each bowl.