1Wash and pick over the beans. Put the beans to soak for 2 to 4 hours in a saucepan in enough cold water to cover by 2 inches.
2Add enough water to cover the beans by 1 inch as they will have absorbed much of the soaking water. Bring to a boil, cover, and cook until the beans are tender, about 2 hours.
3In a skillet heat the oil and sauté the onion and bell pepper until both are soft. Add the garlic, cumin, sugar, and the pimientos, if using instead of bell pepper. Sauté for a minute or two, then stir into the beans.
4Season with salt to taste, and cook, partially covered, over low heat for 1/2 hour longer.