Police say Lauren Cunliffe put little Mowgli in the microwave for punishment after coming home to find her goldfish on the floor in several pieces.
Cunliffe set the microwave for five minutes but had second thoughts and took the black and white kitten out after a minute.
Then she tried to cool off the animal by holding it under running water.
The cat survived the initial ordeal, but veterinarians confirmed it died a grotesque death a couple of hours later.
At her sentencing in Barnsely, England the judge told her, “this was an act of utterly horrendous cruelty on your part on an animal that, as far as I could see, had come to trust you and rely on you."
The BBC reports it may not be surprising that Cunliffe pulled the ugly stunt.
Her own family told the court she suffered from a history of "psychotic depression."
At the hearing one of her relatives went so far as to stand up and shout “"she doesn't know what's happening, she hasn't a clue." Another called it “a failure of medical services, judge."
Cunliffe will serve 14 days in jail and has been told she is prohibited from owning a pet again for the rest of her life.