Rhonda Thomas had taken in James Williams because he was homeless.
When Thomas turned up dead in January inside her burning apartment, police said Williams was the first suspect.
Williams, 42, later confessed to killing Thomas, police said Thursday, as a Sedgwick County district judge ordered him to face trial on charges of first-degree murder and aggravated arson.
Williams pleaded not guilty, after his lawyer argued that there was no evidence of premeditation necessary for first-degree murder.
Judge Eric Yost ruled during the preliminary hearing that premeditation was a question a jury needed to answer.
Detective Blake Mumma testified he talked to Williams on Jan. 31, two days after the fire at the Riverwalk Apartments, 2703 S. Topeka.
Mumma said neighbors had described Williams. Police also found a security video of Williams at a QuikTrip, buying a plastic gasoline container and fuel, which were later found in the burning living room of Apartment 207.
According to Mumma's account of the interview:
Williams said he and Thomas, 52, got into an argument. She pushed him and called him a racial slur.
"'I just snapped,' " Mumma recalled Williams saying.
"He was sincerely apologetic and seemed remorseful," Mumma testified.
Williams also admitted to setting fire to the apartment, Mumma said.
Thomas' body was discovered in her bedroom by firefighters responding to a call by a neighbor.
Sarah Collins lived next door and awoke to find her apartment filled with smoke. She testified that she called 911, grabbed her 4-year-old daughter and got out of the apartment.
Capt. Jarrod Menges of the Wichita Fire Department remembered his colleagues asking for ventilation as they battled the blaze in the living room amid thick smoke.
Menges testified he went into the bedroom to open a window, when he felt something with his foot. He said it was the body of a woman, partially clothed and covered with blankets.
"I yelled, 'We have a victim,' " Menges said.
Menges said the woman had been dead for some time. Menges and others carried the woman outside. She had some burns, Menges said, but he also noticed a large open wound on the woman's forehead.
Mumma said police also noted Thomas' truck was missing. The 1988 pickup had broken down near I-135 and I-235.
Mumma and detective Tom Fatkin later heard Williams describe how he took a bus from Wichita to Emporia.
Authorities would later report being alerted to Williams' presence just north of Delia in Jackson County by a man who gave him some beef jerky and a bottle of water.
After Williams led a chase through Cross Creek, he was captured. He was taken to a Topeka hospital with frostbite after running through the cold water in January.
That's where Mumma and Fatkin talked to Williams.
Yost tentatively set trial for June 14. It likely will be continued to a later date.