Rinse and sort beans. Place beans in large pot; add enough cold water to cover by 3 inches. Let stand overnight. Drain beans and return to pot. Add 3-1/2 cups water. Bring to boil. Adjust heat so liquid barely simmers. Cover and cook until beans are tender, stirring occasionally, about 1-1/2 hours. Season to taste with salt. Heat oil in heavy skillet over low heat. Add onion, Sherry and garlic. Cover and cook until onion is soft, stirring occasionally, about 15 minutes. Add bell pepper, carrot, celery, cumin and coriander. Cover and continue cooking until vegetables are tender, stirring occasionally, about 15 minutes. Add vegetable mixture to beans. Stir in orange peel, pepper and 1/4 teaspoon red pepper flakes if desired. Place rice in bowls. Spoon soup over. Top each with dollop of sour cream or yogurt. Garnish with chopped cilantro and serve. Serves 6. Recipe by: Bon Appetit, October, 1987 Posted to recipelu-digest by "Christopher E. Eaves" on Feb 25, 1998