Combine water and sugar in medium saucepan. Bring to boil on medium heat. Boil 3 min. or until the consistency of a thin syrup. Stir in OREO Base Cake; cook 2 min. or until base cake is completely absorbed, stirring constantly with wire whisk.
Pour through strainer into medium bowl. Immediately add chocolate and butter; stir until completely melted. Gradually add cream, stirring until well blended.
Serve warm as a topping for ice cream, cakes or other desserts.