Cook soba as package directs, rinse and set aside to drain. Place the kombu and water in a medium soup pot, cover and bring to a boil. Reduce the flame and simmer for 5 minutes. Remove the kombu and set aside for future use or discard. Reduce the flame to low and add the shoyu soy sauce. Simmer uncovered for 4 to 5 minutes. Place the noodles in individual serving bowls and ladle the shoyu broth over. Garnish each bowl with an equal amount of scallions and serve.
Per serving - 221 calories, 2 g fat (6% calories from fat), 9 g protein, 40 g carbohydrate, 3 g fiber, 0 mg cholesterol, 496 mg sodium