Heat oil in a medium skillet and sauté onions for 2 to 3 minutes. Add all remaining ingredients and bring to a boil. Reduce flame to medium-low and simmer 5 to 7 minutes. Serve hot or chilled.
Per serving - 156 calories, 2 g fat (14% calories from fat), 7 g protein, 26 g carbohydrate, 7 g fiber, 0 mg cholesterol, 167 mg sodium