In a medium saucepan, bring broccoli and chicken broth to a boil. Reduce heat and simmer uncovered 10 minutes or until broccoli is tender. Mix together flour and milk until flour is dissolved. Add to saucepan. Heat and stir until thickened, about 5 minutes. Turn of heat. Stir in cheese shreds, if desired, until melted in. Serves 3 lunch portions.