Preparation Heat water and sugar in a 2-quart saucepan over moderate heat, stirring, until sugar is dissolved, then cool to room temperature. Stir in lime juice and chill, covered, until cold, about 3 1/2 hours. Pour about 3/4 cup lime cordial in a tall glass filled with ice and top off with beer or club soda. Cooks' note:Lime cordial, without beer or club soda, keeps, covered and chilled, 5 days.