In a nonreactive soup pot, saute the onions in the oil on medium heat for 4 or 5 minutes. Add the cabbage and the chile or cayenne and continue to saute, stirring often, until the onions are translucent, about 8 minutes.
Add the grated ginger and the water, cover the pot, and bring to a boil. Stir in the sweet potatoes, sprinkle with salt, and simmer for 5 or 6 minutes, until the potatoes are barely tender. Add the tomatoes, okra, and lime juice. Simmer until all of the vegetables are tender, about 15 minutes. Stir in the cilantro and add more salt to taste.
Sprinkle the stew with chopped peanuts. Top with a few sprigs of cilantro, if you like.
Serve the stew on rice or with a fresh crusty bread