An apparatus and a method of enhancing boiling heat transfer therein capable of increasing both the critical heat flux and nucleate boiling heat transfer of a working fluid. The method includes placing free particles on a surface so as to define narrow corner gaps and cavities at interfaces between the particles and the surface and heating the surface while the surface is contacted by the working fluid to bring the working fluid to a boil, with the result that bubble nucleation is facilitated and nucleate boiling heat transfer from the surface is increased.