James Miller, one half of the pair responsible for starting up the Sumo Salad franchise back in 2003, was found dead by his flatmate, Nasser Elkordi in their Elizabeth Bay, Sydney home on Sunday night.

According to both The Sydney Morning Herald and The Australian, it is believed that Miller died from an accidental overdose, and his death is not being treated as suspicious.

An autopsy will establish the cause of death.

Upon returning from New York Miller and business partner Luke Baylis started up the first Sumo Salad outlet for $200,000, reports The Australian.

Within just five years, the chain recorded annual revenues of $30 million.

There are now 99 Sumo Salad outlets located throughout Australia. In December 2012 Miller sold his stake in the business; Baylis now owns 40 percent of the company and 60 percent of the business was sold to private equity firm, the Tulla Group.

Miller was also responsible for starting up the Drink’n’Dine company and transforming a number of Sydney’s inner city pubs into trendy nightspots and eateries with business partner Jaime Wirth.

The pair successfully relaunched the Carrington Hotel, The Forresters, The Norfolk Hotel and The Abercrombie Hotel, and just last month they opened Santa Barbara, a bar and restaurant in Kings Cross.

”I will remember James as an endlessly energetic, generous and intensely loyal friend,” said Millers business partner and friend, Jaime Wirth in a statement.

“He had a fierce business drive and intelligence but also a real understanding of what was important to him – friends, family and enjoying every day. I learned a lot from James in business, friendship and life and I will miss him greatly,” he said.

Miller leaves behind a four year old son, Xavier.