Rowson was also overheard on CCTV confessing to friends he thought he had “killed someone”.
He was convicted of murder last month following a 12-day trial at Stafford Crown Court.
Judge Avik Mukherjee said Rowson had submitted his victim to a “fierce, sustained and relentless attack”. He described Mr De Naray as “warm, kind-hearted, compassionate and courageous”.
The judge added: “He was a vulnerable and damaged person who struggled with alcohol. He was struggling every day, but he was a survivor, and was surviving every day until he met you at hospital. He was very vulnerable and was unable to protect himself.”
In a victim impact statement, Mr De Naray’s father, a former shipping and oil executive, said his son’s death had a “devastating” effect on the family.
“Alexis, my wonderful boy, did not deserve to lose his life prematurely and in such a violent way,” he said. “He was a dear son who will be forever missed. Losing him has had a life-changing effect on us as a family.
“He was a very talented chef and worked for many years in London until he became unwell. He was gradually getting better when he sadly and unexpectedly lost his life.”
Gordon Ramsay Holdings had hired Mr De Naray to work at the celebrity chef’s Michelin-starred Claridge’s restaurant, where he rose to the position of chef de partie by his early 20s.
Mr De Naray left Claridge’s to become head chef of Bunga Bunga in Battersea, south-west London.