A man accused of killing his partner Alexis Parkes in a house fire has been found guilty of murder.
James Morton Mason told police he set a car alight underneath Ms Parkes' house in Brisbane's south in February 2020 following an argument.
The 46-year-old pleaded guilty to arson at his Brisbane Supreme Court trial which began last week.
However, Mason pleaded not guilty to murder after telling officers he did not consider the consequences of the fire and didn't intend to hurt his partner of 11 months.
Ms Parkes, 50, died days after firefighters found her unresponsive in her Chermside house.
She passed away after suffering multiple organ failure due to injuries from the blaze.
Mason told police he started the fire after claiming Ms Parkes had threatened him and his family during an argument.
In a recording played in court, Mason was asked by an undercover officer at the Brisbane Watch House what he was thinking when he started the blaze.
"I will get you back bitch, you don't f***ing threaten my family," Mason said.
Mason then shared a joke about getting marshmallows for the deadly blaze with the undercover officer who he thought was a fellow inmate.
After starting their deliberations on Thursday, the jury found Mason guilty on Monday.
Mason is set to be sentenced by Justice David Jackson.
