A teacher at a childcare centre in Ang Mo Kio did just that to a child left under her charge in May last year.

But things went terribly wrong when the boy, aged four then, ended up with rashes on his face and neck. His mouth and lips were also left mildly red after coming in contact with his teacher's chilli-stained hands.

The sight of the boy's red face and watery eyes prompted his mother to lodge a police report after she picked him up from the centre.

At 7pm that day, his teacher Hasanah Ahmad, 25, noticed the boy about to throw a wooden stick playfully in the direction of her three-year-old son, who also went to the same centre.

She panicked and shouted at him to put the stick down before taking him to a classroom to reprimand him. Instructing him to wait there, she switched off the lights and left. She returned with a packet of chilli padi and threatened to make him eat it when he refused to look at her.

The boy kept quiet initially but started struggling when she tore open the packet and pointed at the fiery chilli padi. During the scuffle, the contents came into contact with his mouth and face.

Another teacher heard the commotion and walked in to see chilli padi on the floor and red patches around the boy's lips.

Hasanah pleaded guilty on Monday to ill-treating the boy and causing him unnecessary suffering.

Hasanah will be sentenced on Friday. Her 27-year-old husband, a policeman, as well as other family members were present in court on Monday.