Pick through beans to remove bad beans. Soak beans overnight in cold water. Drain and rinse.
In a large soup pot or dutch oven, stir together the beans, water, green pepper, onion, vegetable oil, bay leaves, garlic, and salt. Bring to a boil, cover, and boil for 1 hour.
Reduce heat and simmer, covered, for 3 to 4 hours, or until beans are very tender. Stir occasionally and add water if needed (if water level drops below the top of the beans).
Remove about ⅔ of the beans and set aside. Use a spoon to mash the remaining beans against the side of the pot. Return the set-aside beans to the pot, stir, and heat through.
Remove bay leaves and stir in vinegar or lemon juice when ready to serve.
Serve over rice. Garnish with sliced pimento and lemon wedges.