Bring water to a boil, add the couscous and stir. Cover and turn the flame off. Allow to couscous to steam for 5 minutes. Remove and fluff with a fork to cool. Add the vegetables, garbanzo beans and pistachios. Mix thoroughly.
To prepare the dressing, place umeboshi paste, tahini, scallions, parsley and water in a blender. Puree until creamy. Serve over the salad.
Per serving - 403 calories, 17 g fat (38% calories from fat), 7 g protein, 48 g carbohydrate, 7 g fiber, 0 mg cholesterol, 218 mg sodium