Wash beans thoroughly and soak overnight in water. Use this water for cooking. Saute onion, green pepper and garlic in olive oil. Combine all ingredients except the vinegar which is added a few minutes before beans are ready to serve. Cook over low heat until beans are tender and the liquid is of thick consistency. Liquid can be thickened by taking out a few beans (1/4 to 1/2 c) and process in blender or food processor; then return to pot and stir to thoroughly mix.