"When a delivery guy leaves to make an order, he'll yell out to the rest of the team where he's going, and they will yell back 'Go! Go! Go!'" And when they get back, he adds, "they shout out the time - keeping that time consciousness".
"Eighty percent of our business is delivery orders," he says, so his guys on the motorbikes are at least as important as the team in the kitchen.
Gray does a quick demonstration of how he trains delivery drivers to knock on a door and handle themselves. "The encounter with the customer only lasts about 30 seconds," he says, "but in that 30 seconds you either win or lose the game."
The interesting thing about pizza, he says, is that it was a good cultural fit with China.
"In China, you have a round table, all the food is in the middle and everybody's reaching in for their food, right? Whereas in the West, with other foods, you order your own plate." Pizza is a food that both cultures eat the same way, he says.
An entrepreneur at heart, Gray has set up several ventures in China, including Lush Cafe/Bar, Pyro Pizza, the party brand Yen as well as Gung Ho Pizza. For three years, he was also an adviser to an initiative to assist key New Zealand companies enter the China market.
Gray has been busy with some social projects as well as his businesses.
He co-founded Peking Pups, a charity that supports organizations that help stray dogs, and in 2003 set up Flower Power, which raises money to buy food and clothing for the flower-peddling street children in the Wudaokou area of the capital.
"I am happiest exploring the wilder parts of China," he says, adding that he has jeeped or motorbiked around most of the country. He's also keen on adventure sports, competing in the Phuket Triathlon in 2011 (team) and 2012 (individual).
"When I am not on my bike delivering pizza, or selling my body off for a good cause," he proclaims on his LinkedIn profile, "I can be found up at my Gung Ho Hut (a boutique hotel) at the Great Wall of China in Jiankou village, where I am currently running for mayor."