Drain beans, saving liquid.
Peel onion and slice paper-thin. Heat oil in large heavy saucepan. Add onion, green pepper and beef. Cook,
stirring constantly and breaking beef apart, until beef is lightly
browned. add beans, tomatoes, tomato sauce, chili powder, salt, bay leaf and cayenne.
Cover and cook gently 1 1/2 hours. Add some of saved bean liquid if necessary (
mixture should be the consistency of a very thick soup at the end of cooking).
