Wash and pick over the beans. Cover with water and soak overnight; drain.
Heat the oil in a large pot. Add the onion and saute until tender, about 5 minutes. Add the chili powder, salt, beans, and 5 cups water. Bring to a boil. Reduce the heat, cover, and simmer until the beans are tender, 1 to 1 1/2 hours.
Add the green chili sauce; stir and simmer, uncovered, 30 minutes longer. If the mixture is too soupy, simmer a few minutes longer to reduce the liquid.
This recipe yields 9 servings. Serving size: 2/3 cup.
Exchanges Per Serving: 2 Starch, 1 Vegetable.
Nutrition Facts: Calories 190; Calories from Fat 12; Total Fat 1g; Saturated Fat 0g; Cholesterol 0mg; Sodium 218mg; Carbohydrate 35g; Dietary Fiber 13g; Sugars 4g; Protein 11g.