On medium heat, In a saucepan combine peaches, water and sugar. Bring to a low boil and then turn on low. Cook until your desired texture. Add extra water as needed. Pour a great portion of hot liquid in to a bowl (no fruit). Put about a tbsp. Of cornstarch and blend well. Pour over fruit and continue to cook until you have a thick consistency. Let it cool then pour on top of cheese cake a refrigerate.