Judge Davis asked Bevin to keep his language appropriate to the courtroom, then continued.
"You punched her multiple times to the head, with a clenched fist and using full force ... You then interrupted your attack to get a recently-made cup of coffee and poured it over her head and front."
Bevin trapped the victim in a corner where she couldn't escape, and when she fell to the floor he continued to punch and kick her repeatedly, Judge Davis said.
At that point Bevin interrupted again to dispute the court's version of events.
"Your honour, f***, if I'd done that, her head would've been like a pumpkin," he said.
Judge Davis silenced him again and told the court how Bevin had then poured the contents of a recently boiled jug over her back, which was protected only by a T-shirt.
When Bevin launched another expletive-laden interjection Judge Davis halted proceedings and had him returned to custody, saying his constant interruptions made sentencing impossible.
Earlier Bevin's lawyer, Doug Blaikie, said his client's life had been blighted by "various addictions" and he was distressed when shown photos of his former girlfriend's injuries.
"He said, "I'm sick of hurting people', but he needs to cure his addictions."
Crown lawyer Bernadette O'Connor, however, was unconvinced by claims of Bevin's remorse.
He had continued using alcohol, cannabis and methamphetamine after his last treatment for addictions.
"The victim will carry around the scars of what he has done for many years to come," she said.
A second attempt at sentencing is scheduled for June 6.
Bevin had earlier pleaded guilty and accepted the summary of facts.
A sentencing indication suggested a prison term of six years or more was likely.