Mr Walker, 27, originally from Napier, has been living in London for five years. He was managing a two Michelin star restaurant in upmarket Notting Hill on Monday night, when a mob attacked, and he had to take decisive action to protect restaurant patrons.
He said about 20 youths smashed their way into The Ledbury at about 11pm, when he had around 30 guests in the restaurant.
"I told all the guests to get away from the windows. By that stage the rioters realised it was a restaurant and there were people inside. They started kicking at the door, throwing bottles, used a broomstick and then a brick."
"They started yelling for everyone to get down and demanded they take their valuables off. They smashed tables over, and were coming right up to peoples' faces and taking necklaces off, taking their wristwatches, rings, wallets and cellphones."
They also robbed the staff of their phones, and the cash draw.
He said the kitchen staff then came roaring out, some armed with rolling pins, and a few punches were thrown between the rioters and kitchen staff.
The rioters then went outside, where there were about 70 other youths, who then chased the police who had just arrived on the scene.
"I was worried that the rioters where going to come back, so I ushered everyone into the wine cellar. We barracked the doors, by that time there was enough guys to protect the guests, if we needed too." Mr Walker said.
He kept the guests in the restaurant until he felt it was safe to send them home, he said his main concern was their personal safely.
He offered whisky and champagne to calm their nerves, and called them taxis to get them home.
He and his staff were praised by the restaurant-goers the following day, they were sent chocolates, letters and champagne.
Mr Walker was also inundated with emails, which he said thanked he and his staff for keeping calm and "going above and beyond their duties".
The Ledbury was open for lunch the following day, but decided to close for dinner, as Mr Walker did not feel the risk would be worth it, if another mob attacked.