Dale Bolinger, 58, bought an axe from a DIY store in Broadstairs, Kent, the day before he planned to meet the girl, who he groomed online.
He chatted with the teenager, a Mexican girl called "Eva" said to be living in Germany, on a website called the Dark Fetish Network (DFN).
In conversations, Bolinger described sex acts he wanted to perform on her and how he would murder her, which she said she wanted to happen.
After a four-day trial at Canterbury Crown Court, Bolinger was found guilty of attempting to meet a girl under the age of 16 following sexual grooming, after three hours of deliberation by jurors.
In online chats, father of three Bolinger told "Eva": "The idea of us making love and then eating you is a VERY great turn on!
"I have been called a very generous lover and I would be very generous to you before I prepped you for the table."
The night before their meeting, Bolinger - who worked as a registered nurse at the Queen Elizabeth The Queen Mother Hospital in Margate - told her: "Got the axe, you ready to get that train?"
But jurors heard that "Eva", whose true identity has never been uncovered, failed to show up at Ashford International Station as planned.
Before the trial, Bolinger admitted other charges, including administering a poison or noxious substance after he put a cloth soaked in dry cleaning fluid over his friend Urlene King's mouth in July 2010.
He also pleaded guilty to one count of making indecent pseudo photographs of children, and seven counts of publishing an obscene article.
Judge Adele Williams adjourned sentencing to September 19 after asking for a psychiatric and a pre-sentence report to be prepared to "assess the level of risk the defendant poses to the public".]
Prosecutor Martin Yale told the trial that internet chats involving Bolinger on the DFN site about beheading and eating women and girls were discovered by the FBI in New York.
Investigators discovered the email address firstname.lastname@example.org was being used in Kent and Bolinger was arrested after the information was passed to Kent Police.
In chats with other users, Bolinger - who used a picture of supermodel Naomi Campbell on his profile - claimed to have eaten a 39-year-old black woman and a five-year-old child, Mr Yale told jurors.
His profile, under the name Chris C, listed his interests as "cannibalism, mainly the hunting and preparation of young but sometimes not so young women".
Mr Yale read out chat logs between Bolinger and users in which he referred to beheading a 14-year-old, eating children while their mothers watched, and cooking and eating a pregnant woman and her foetus.
Bolinger told the court he did not believe "Eva" - who used the surname "Gonza" but later told him it was "Nada" - was a 14-year-old girl.
He told police he believed "Eva" was probably a man in his 30s "surrounded by pizza boxes" who would be dead by his 40s. And he denied that he would ever decapitate someone in reality.
But Mr Yale said it was clear Bolinger did believe "Eva" was a 14-year-old girl, and he had bragged to others in chat logs about the proposed meeting in Kent with her.
The court heard that Bolinger had taken his fantasies beyond chat rooms before. In July 2010, he put a cloth soaked in dry cleaning fluid over friend Ms King's mouth.
Following his arrest at the hospital where he worked after the emergence of the graphic chat logs, police found at his home indecent pseudo-images of children aged four to 16 which had been digitally manipulated.
The titles for the pictures included "Dinner", "The BBQ", the "BBQ2 and the "BBQ3". Mr Yale said these pointed to Bolinger's sexual interest in cannibalism relating to children.
Bolinger was asked by defence counsel Paul Jarvis whether he had ever attempted to kill anyone, eaten human flesh or sexually assaulted a child.
He replied: "No, not in reality, just in fantasy."
In his closing speech, Mr Jarvis said: "We say that when you look at all the evidence, it's quite clear that Mr Bolinger is far more Walter Mitty than Hannibal Lecter.
"He is a fantasist and sometimes he goes too far and sometimes he stops, and sometimes - when the person encourages him - the fantasy continues."
The court heard that Bolinger told police he had bought the axe from Homebase to remove two tree stumps from the side of his house.
He said he had only gone to Ashford International Station to meet "Eva" because he was concerned for her safety.
He "probably would have wet" himself if she had turned up and he would have called social services or the police, he added.
Bolinger said he visited the DFN website out of curiosity and that the people he spoke to seemed "willing to accept anything".
He told the jury: "Initially, I was looking to find people with like minds and to see where they came from, but it soon spiralled down into trying to shock people enough that they would ask 'is this fantasy?'"
In police interview, he said he started having fantasies about cannibalism at about the age of six, and he blamed his "very domineering" mother for his "weird" behaviour.
He told officers: "By the time I got to 14, I turned into the villain of the piece and I wondered what it would be like to eat a girl."
Bolinger told police he had never discussed his fantasies with his wife of 34 years, Rosemary, or their children, and said he felt ashamed.
"It was less to do with sexual gratification and more to do with anger," he told officers. "The people that do it (cannibalism) are seriously deranged, and I may be many things but I am not deranged."
He also admitted in interview that discs found in his home containing indecent images of children were his, the jury heard.
Mr Yale said one image featured a girl aged between six and nine lying naked on a serving plate with an apple in her mouth, and others were of a similar nature.
When questioned about the images, Bolinger, formerly from Canterbury, told police: "I do not find children sexually attractive but I do find them interesting as a food source."
Detective Inspector Rob Chitham, of Kent Police, said after Bolinger's conviction: "This was a long and complicated investigation because much of the evidence was in the USA.
"In addition, the people who use fetish chatrooms go to great lengths to hide their identity, and specialist knowledge and equipment is needed to determine who they are and where they live.
"We worked closely with the FBI and other law enforcement agencies in America to identify one of the chatroom users as Mr Bolinger. A painstaking search for evidence both at his home and elsewhere then began so that we could bring him to justice."