Clare Smyth, chef/proprietor of Restaurant Gordon Ramsay in London's Chelsea, has become the first female chef in 15 years to score 10/10 in the 2015 edition of the Good Food Guide.
Gunn Eriksen was the last female chef to achieve the score at the Altnaharrie Inn in Loch Broom, Ullapool, in 1999.
Restaurant Gordon Ramsay joins Simon Rogan's L'Enclume and Heston Blumenthal's the Fat Duck as the third of only three restaurants in the country to hold top marks in the Guide.
L'Enclume has achieved top marks for the second year running, while the Fat Duck has now held the score for seven years in a row - longer than any other restaurant.
There are five London restaurants in the top ten, including Claude Bosi's Hibiscus, Jason Atherton's Pollen Street Social, the Square, Brett Graham's the Ledbury and Restaurant Gordon Ramsay.
Clare Smyth at Restaurant Gordon Ramsay said: "This is incredible, I'm absolutely overjoyed, we all are. I have personally referenced The Good Food Guide for places to eat for years and value their opinion as it's the customers' opinion.
"It makes it so much more significant when you know it's through customer feedback. Like all restaurants we are one big team and my team here is tremendous, so a huge thank you from every one of us."
Elizabeth Carter, consultant editor of the Waitrose Good Food Guide, added: "After a break of a decade, Gordon Ramsay's Chelsea flagship has once again been awarded a perfect 10. Now the domain of Clare Smyth, with support from what is, without doubt, one of the best front-of-house teams in the UK, this most impressive of London's premier restaurants is back in that elite club.
"Further congratulations, too, for Smyth is the first female chef to achieve our top score in 15 years."
Meanwhile, Claude Bosi, who moved up from seventh to fifth place, commented: "This is an exciting result for my team, and proof that all of our hard work and dedication - to both the quality of food and service - is paying off with improved recognition among the top five in the country."