Place beans in a large saucepan or Dutch oven; add 4 1/2 cups water.
Do not drain.
Blend 1/2 cup cold water slowly into flour; stir into beans.
Cook and stir till bubbly.
Stir in undrained tomatoes, celery, carrot, onion, salt, Worcestershire, and bay leaf.
Crumble ground beef into beans.
Bring mixture to boiling.
Bake, covered, at 350° for about 1 1/2 hours, stirring occasionally.
Discard bay leaf.
Skim off fat.
Season to taste with additional salt and pepper.