He describes both of these ideas beginning at about 1:50 into this video:
At about five seconds into the video, there is a picture of his stove and pots. But those may or may not be the pots he describes later in the video.
Are there specially designed pots that allow for the sort of stacking he describes? Or is he using his pots in his own innovative way? Does anyone know of pots designed for this? Or pots that work well when stacked as he describes?