Before leaving for work, add the 2 ingredients: red dates and dried longan and very hot water into a vacuum flask. Secure the top. Bring the vacuum flask to work. By mid morning, you will have a nice hot flask of sweet soup. Dried longan helps blood circulation and is good for ladies who feel cold during their menstrual cycles. Red dates is good for an easily irritable stomach. Both dried longan and red dates are very sweet. It is therefore not necessary to add any sugar.