1. In large saucepan fitted with steamer basket, bring 2 inches water to a boil over high heat. Add sweet potatoes, cover and steam until tender, about 10 minutes. Set aside and keep warm until needed.
2. In large, heavy pot, heat oil over medium heat. Add onion, ginger, garlic, scallions, red peppers, 1/2 teaspoon salt and curry powder. Stir, cover and cook 3 to 5 minutes. Stir in chickpeas (with liquid) and simmer, uncovered, 5 minutes.
3. Add vinegar and remaining 1/2 teaspoon salt. Stir in sweet potatoes. Over low heat, gently stir mixture about 2 minutes to allow sweet potatoes to release some of their starch. Be careful not to break them up completely. Add cilantro and stir to blend. Serve hot.