But less than a month later the 27-year-old hung up his apron and took four other staff members with him after the owner asked them to move from serving scallops with veal sweetbreads, one of its specialities, to food normally served in pubs.
"We were all overwhelmed by winning the Michelin star. It's a great achievement," said Simpson.
"But just after winning it, the owner said he wanted to change the whole concept of the restaurant.
"He wants to change it into a pub and serve burgers and chips."
The restaurant specialised in modern British cooking with a French twist, and it was dishes such as muntjac deer with lobster and pan-roasted wood pigeon that won over the Michelin judges.
Due to the staff walk-out the restaurant had been forced to close, a spokesman for the owner said, but would reopen in March as a pub.
Simpson said he hoped to relocate the restaurant, under a different name, to new premises.
The Michelin has been the top food guide for more than a century, and winning its top three-star accolade is regarded as a major achievement for a restaurant.
There are 140 restaurants in Britain and Ireland which have been recognised by the guide with one, two or three stars.
The Michelin "Red Guide" began in 1900 as a way of promoting tyres and guiding owners of the first motor cars to France's best restaurants.
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