Anandakanda 2.5.38

2.5.38

tatpiṇḍaṃ triphalātoyaiḥ piṣṭvā ruddhvā puṭe pacet /
ṣoḍaśāṅgulagartāntar nirvāte 'harniśaṃ pacet //

Grinding that lump with triphalā water and sealing it, one should cook it in a pit; / inside a sixteen-aṅgula pit, free of draft, one should cook it day and night.