St John sent an ambulance and a rapid response team to the scene and took her to Christchurch Hospital emergency department with facial injuries.
The Fire Service attended but only provided medical assistance until the ambulance arrived.
A spokeswoman for Munchie Express said while the unnamed worker was shaken up by the incident, she was more embarrassed than anything.
"She just didn't light it properly. It was a simple mistake," she said.
"I'm about to go pick her up from hospital. She's got minor, superficial burns but she's ok.
"She says she'll be back in tomorrow, even though I said to take the day off. She's a tough cookie."
Foodstuffs declined to comment.
The Government's labour service is investigating.
