LONDON — When George Benjamin’s opera “Written on Skin” opened in 2012, it was immediately acclaimed as a masterpiece. One critic suggested that it was one of the defining works of the 21st century.

What made the event even more remarkable was that it was only Mr. Benjamin’s second attempt at opera, and his first large-scale work in nearly a decade. For a composer whose painstaking process had become mildly notorious — he took the better part of 10 years to complete a single 15-minute piece, dryly called “Sudden Time” — there was a sense that a dam had burst.

Sitting at his kitchen table in West London recently, Mr. Benjamin still seemed a little stunned — not so much by the reaction to the opera as by the fact that he’d been able to compose it at all.

“A piece on that scale, an hour and a half of music — these are things I’d never felt able to attempt before,” he said, then smiled shyly. “It was a very long wait.”