A man filled a bucket with boiling water during a smoko break and "calmly" poured it over the back of a colleague's head, neck and shoulders.
Kian-Wee Show then sat down and continued eating his lunch while his victim jumped up and ran to the first aid room.
Show, a 28-year-old Malaysian national on a work visa, pleaded guilty to a charge of wounding with intent to cause grievous bodily harm.
He was sentenced to five years and seven months in jail yesterday when he appeared in Napier District Court.
The incident happened in the staff cafeteria of the Turners and Growers packhouse in Whakatu, near Hastings, on July 25 last year.