In a heatproof bowl, pour boiling water over cranberries or submerge them
in a pot of boiling water off the heat. Let them sit until the skins pop.
Do not let the berries boil; drain immediately.

Arrange berries on baking sheets, sprinkle with granulated sugar and freeze
for 2 hours (the freezing also helps break down the cell structure, which
promotes faster drying and a more tender dehydrated cranberry).

Arrange frozen berries in a single layer on mesh sheets in drying trays.
Place drying trays in dehydrator and dry at 140 degrees until dry, about 10
to 16 hours, depending on the make of the dehydrator. The cranberries may
still be sticky and should definately still be chewy, but with no pockets
of moisture.

~From "Mary Bell's Complete Dehydrator Cookbook"