Arrange beans and onion slices in steaming rack. Place over 1/2 cup boiling water; cover and steam 25 minutes or until crisp-tender. Remove from heat, and discard onion slices.
Saute 1 tablespoon chopped onion in butter until tender; add beans and chicken broth. Cover and simmer 15 minutes. Add parsley, salt, and pepper; simmer an additional 2 minutes.