It might seem unusual that a chef didn't step foot in a restaurant until he was 15 years old but this didn't stop Leon Rothera from going to work in a Michelin-star kitchen and cooking for the stars.

Rothera had what he calls "a bit of an alternative upbringing," spending his early years being homeschooled at his family's cottage in Northumberland, in the northeast of England.

He describes his father as a "hippy rebellious type," who'd had a strict upbringing and so decided to raise his family in a little house in a rural setting with no electricity, and to "live off the land."

Rothera compares the experience to the popular 1970s British TV show "The Good Life," a series which depicted a couple leaving behind the rat race of London to live self-sufficiently in the suburbs.

He tells CNBC this is where his "connection with food" originated, seeing his parents make homemade bread and growing their own vegetables.

At age 16, Rothera enrolled at sixth-form college, the British equivalent of a senior high school, to study cooking. Shortly afterwards he moved down to London to work at The Lanesborough — at one time said to be the world's most expensive hotel.

From there, he went to Michelin-star restaurant No.1 Lombard Street, becoming chef de partie, effectively fourth-in-command, at just 19 years old.

But Rothera says he was always dreaming up his own ventures and so at 21 years old, he set up a dinner party catering business, serving up meals for big names like "Love Actually" actor Bill Nighy.