The twisted teenager who allegedly beheaded his mom’s boyfriend in Staten Island scooped the victim’s brains out with a spoon and put them in a blender, police sources said.

It wasn’t clear what Damien Hurstel intended to do with the gray matter, which was found in the kitchen appliance at the scene, the sources said.

Cops said the 19-year-old confessed to stabbing his mother’s live-in boyfriend, Anthony Casalaspro and sawing off his head inside the family’s Cary Avenue home in West Brighton on Oct. 6.

Damien Hurstel said little during a court appearance Friday. LP Media

The 45-year-old victim’s remains were found with a plastic soup ladle on the torso, and his head beside him with a spoon sticking out, a photo obtained by The Post showed. 

Hurstel, who is facing second-degree murder, manslaughter and weapons charges, was transferred from a hospital to solitary confinement in Rikers Island jail earlier this week, said his lawyer Mark Fonte, who met his client in a room Friday before a hearing in Richmond County Supreme Court.

“It was chilling,” Fonte said of meeting the teen in person.

Hurstel is charged with allegedly killing his mom’s beau in the family’s Staten Island home and then sawing off his head and putting his brains in a blender, police sources said. Luiz C. Ribeiro for New York Post

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“He was having a real difficult time separating fantasy from reality,” said Fonte, who entered a not guilty by reason of insanity plea. “He wasn’t sure what really happened.”

Fonte asked the teen why he ended up going to the hospital after his arrest and Herstel said he thought he had been in a fight.

The teen’s mom, Alicia Zayas, told The Post the doctors who were treating her son at Richmond University Medical Center changed his medication and didn’t tell her. Obtained by the NY Post

“’I think I might have fought two other people in there,’ ” Fonte recalled his client telling him. “ ‘I remember punching one in the face but I’m not really sure that happened. I don’t know if that’s like something I’m imagining, or if it really happened.’ ”

Herstel also wasn’t sure if he was taking medication at Rikers, the lawyer said.

The teenager showed his sister the bloody scene in the family’s bathroom after he beheaded Casalaspro and asked the 16-year-old if she wanted their mother to live, mom Alicia Zayas, 39, exclusively told The Post.

The mom said Casalaspro took her son fishing and tried to help him. Paul Martinka

The mom entered the bathroom looking for her beau and found a grisly scene when she returned home Oct. 6. Kyle Mazza/Shutterstock

“She said, ‘Are you gonna hurt mom?’ ” Zayas said of her 16-year-old daughter Bri’s encounter with her blood-soaked son.

“And he said, ‘Do you want her to live?’

“And she said, ‘Yes, please.’

A photo from the scene shows the severed head lying next to the corpse inside a walk-in shower. Obtained by the New York Post

The disturbed youth is accused of stabbing city Department of Sanitation worker Casalaspro and then beheading him. Facebook/Anthony Casalaspro

The sister then asked if she could leave the family’s bathroom and ran outside to call her mom and warn her.

Hurstel started having hallucinations when he was 13 and drew pictures to show his mom the horrific scenes he was seeing, she said.

Damien Hurstel began taking antipsychotic medication when he was 13 and suffering from gruesome hallucinations, his mom said. Obtained by the NY Post

That’s when he first went on antipsychotic medication, she said.

Zayas monitored Hurstel’s condition through his teenage years, but once he reached 18 she was shut out, the mom said.

Doctors at Richmond University Medical Center changed Hurstel’s medication in January without notifying her, said Zayas, who claimed her son went downhill after the switch. 

The medical center said it doesn’t disclose information about patients or the care they receive.