A St. Paul woman was found guilty of her boyfriend’s fatal December stabbing — prompted by an argument over White Castle food — by a Ramsey County District Court jury Monday.

Melissa Marie Fostvedt, 34, was convicted of second-degree murder without intent in the death of Thomas Calvin Donald Jenkins, 21, of St. Paul.

They fought after failing to buy enough food at White Castle for themselves and Fostvedt’s three children — aged 10, 7 and 4. The argument continued into the kitchen of Fostvedt’s Como neighborhood apartment, where it turned violent, according to the criminal complaint.

Fostvedt and her two older children stated that Jenkins slipped and fell on a knife. But her youngest child said that Fostvedt stabbed Jenkins and pointed at his armpit, charges said.

An autopsy found that Jenkins had been fatally stabbed in the left side of his chest, near the armpit, according to the complaint.

Jenkins’ family said Fostvedt had assaulted him in the past, including a week before he was killed, when she hit and spat on him, charges said.

Fostvedt was acquitted of second degree murder with intent Monday. Her sentencing is scheduled for Sept. 29.