Cuban Black Bean Soup (Sopa de Frijol Negro)

1 cup chopped onion
3 cloves garlic, finely chopped
2 tablespoons vegetable oil
1 pound (2 2/3 cups) dried black beans
3 cups beef broth
3 cup water
1 cup finely chopped fully cooked smoked ham
1 cup chopped green bell pepper
1 large tomato, chopped
1/4 cup dark rum
1 1/2 teaspoons ground cumin
1 1/2 teaspoons dried oregano leaves
Chopped hardboiled eggs
Chopped scallions

Cook 1 cup onion and the garlic in oil in Dutch oven until tender. Add remaining ingredients except chopped eggs and scallions. Heat to boiling; boil 2 minutes. Reduce heat; cover and simmer until beans are tender, about 2 hours. Serve with chopped eggs and chopped scallions.