The 50-year-old kept her eyes closed during much of Monday's sentencing as a court heard her calculated plan to kill four members of her extended family and the lies she told as she tried to cover up the crimes.
But she stared straight ahead as she was given hope of being released while serving three concurrent life sentences.
Victorian Supreme Court Justice Christopher Beale rejected prosecutors' request that she be denied any chance of freedom, sentencing her to a non-parole period of 33 years due to the harsh conditions she faced in custody.
With time already served, Patterson could be back in the community at the age of 82.
She deliberately served beef Wellingtons that were laced with death cap mushrooms to four lunch guests in July 2023, the court heard.
Her former in-laws Don and Gail Patterson, 70, and Gail's sister Heather Wilkinson, 66, all died after consuming the meal, while Heather's husband Ian was left seriously ill but survived.
Patterson claimed it was a terrible accident but a jury in July found her guilty of three counts of murder and one count of attempted murder.
Justice Beale accepted there was no proven motive for the crime, adding it was not his job to speculate about why she committed the murders.
But he found Patterson concocted an elaborate story to cover up her offending, including lying about a dehydrator, where she sourced the mushrooms and having cancer.
The judge also believed Mr Wilkinson, who described how the killer served the individual beef Wellingtons on grey plates to her lunch guests while her own meal was on a small orange-tan plate.
"I find that you did this to ensure that you did not mistakenly consume a poisoned meal," Justice Beale said.
He described Patterson's offending as the worst category of murder, noting the enormous betrayal of trust towards people she considered family.
"They had all been good to you and your children over many years," he said.
"Not only did you cut short three lives and cause lasting damage to Ian Wilkinson's health ... you inflicted untold suffering on your own children whom you robbed of their beloved grandparents."
Patterson would have anticipated the victims experiencing protracted suffering when she chose to use the mushrooms to poison them, the judge added.
He also found her intention to kill extended past the lunch and into the days after, when she did not tell doctors or health department staff where the mushrooms were found.
The severity of her crimes and her lack of pity warranted the maximum jail sentence, Justice Beale said.
"Your failure to exhibit any remorse pours salt into all the victims' wounds," he said.
But the judge accepted Patterson's time in custody would be more difficult as she would likely remain in solitary confinement for years.
"Given the unprecedented media coverage of your case, and the books, documentaries and TV series about you which are all in the pipeline, you are likely to remain a notorious prisoner for many years to come," he said.
Patterson's eyes opened at the judge's comments and she turned towards the media box and scowled.
The only other time she opened her eyes during the hearing was when Justice Beale referred to Mr Wilkinson's victim impact statement, in which he offered forgiveness.
"You would do well to embrace (the offer) in the manner he suggests," the judge said.
Speaking outside court after the sentence, Mr Wilkinson thanked police for bringing "to light the truth of what happened to three good people".
He did not comment on Patterson's sentence but instead praised people from across Australia and the world who had offered their support during the ordeal.
Patterson will have 28 days to lodge an appeal against her convictions and sentence.
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