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A modified assisted-electrode method has been proposed, which can be used to successfully machine through holes in pure and non-conductive ceramics using the electrical discharge machining (EDM) process. The developed method has also been investigated from a theoretical perspective to understand the inherent underlying process and to be able to make suitable machining recommendations according to the desired output. The effect of machining parameters and conductive coating has been studied. The possible material removal method has been investigated using SEM and EDS analysis. A multi-layer coating with conductive copper tape sandwiched with graphene and carbon nanotubes in between the tape worked as a successful assistive electrode setup. The SEM and EDS analysis indicate melting and thermal spalling as possible material removal mechanisms during EDM of electrically non-conductive Aluminum nitride (AlN) ceramics. The deposition of carbon at the edge of the holes indicates the generation of conductive carbon layer favoring continuous sparking during the machining process, and this makes the EDM of non-conductive AlN possible. The walls of the drilled holes become conductive and allow the machining to go through even beyond the conductive layer range. The performance characteristics depend on both the electrical parameters and the assistive electrode setup.