大日經持誦次第儀軌 1.155

1.155

Abiding thus, one first accomplishes the yoga of the iṣṭadevatā. When the meal is finished, the remaining touched food is offered to those who should eat it with the karma-accomplishing hṛdaya-mantra. One should employ the increasing Amoghapracaṇḍa Āryācala mantra, reciting it once; the recipients will rejoice, constantly follow the practitioner, and protect and remember him.