Jang-wa Practice
Rinpoche gave the following explanation of the practice of jang-wa.
Jang-chog means "Purification Ceremony." It is a skilful Vajrayana practice for purifying the negative karma of those who have died, and transferring their consciousnesses to a pure land. It can liberate beings from the lower realms, and can benefit those who have died recently and are in the intermediate state on their way to a lower rebirth, by changing their rebirth to the human realm or a Pure Land. In that way, those beings have a chance once again to meet the Dharma and meet a fully qualified virtuous friend. At the same time, the ashes or remains of the deceased can be blessed, so they actually become holy objects, at which time they can then be placed in holy objects like stupas and statues. This becomes highly beneficial for the deceased and for those family or friends left behind, because every time they make offerings such as flowers or lights and pay respects to the deceased, they create a great deal of merit.
There are a number of sources where Buddha explains or depicts this as being appropriate to do. Also, in the very extensive commentary by Desi Sangye Gyatso (who organized the building of the Potala), he explains the extensive benefits of various actions performed with holy objects. He also quotes sources from the sutra.
This skilful practice that benefits the dead originated with Guru Shakyamuni Buddha. One deva's son died and was reborn in a lower realm. The devas perceived this, and requested Shakyamuni Buddha to help him. The Buddha manifested in the form of a deity named Kunrig, and then all of the practices of this deity, including the Jang-wa practice, were given. The practice of this deity is to liberate sentient beings from the lower realms. Later, the Jang-wa or Purification practice was combined with the practices of other deities such as Amitabha.
The names of the dead people should be written on a large sheet of paper (use thin paper that can easily be burned), and on the reverse side of the paper, write the first letter of the name of each person (e.g."A" for Alice).
We do not offer food to the dead people (as in the Chinese tradition), but we can make offerings of food, flowers, light, etc. to the Three Jewels on behalf of the dead people, to accumulate merit for them. Any food can later be distributed.