Mix water and sugar and cook to a thin syyrup in the top of a double boiler placed directly over low heat.
Mix cornstarch with the cold water and stir into the syrup. Cook until clear. Place over hot water in lower part of double boiler to keep warm until you wish to serve it. Fold in the liqueur and blend well.
Serve over steamed puddings, ice cream or custards.
NOTES : Liqueur could be Cointreau, anisette, crème de menthe or other flavor of your choice