In separate bowls, soak dried daikon and hiziki in warm water to cover for 15 minutes. Chop dried daikon and reserve soaking water. Discard hiziki soaking water. Heat up oil, and sauté onions 2 to 3 minutes. Add dried daikon, carrots, hiziki, and water. Cover, bring to a boil, and reduce flame to medium-low. Simmer 30 minutes or until hiziki is tender. Add shoyu, cover, and simmer 5 minutes. Remove cover, add leeks or snow peas, mix, and cook off remaining liquid. Serve.
Per serving - 65 calories, 2 g fat (25% calories from fat), 2 g protein, 10 g carbohydrate, 3 g fiber, 0 mg cholesterol, 244 mg sodium