Smyth’s restaurant, Core, in west London, previously held two stars, however during Monday’s online ceremony the chef was awarded a third star - the highest amount a chef can achieve.
French chef Hélène Darroze, who runs a restaurant bearing her name at The Connaught hotel in central London, was also awarded three stars.
The virtual ceremony, presented by Davina McCall, nodded to the challenges the industry has faced this past year, praising those who offered food to NHS staff and managed to deliver top-quality food in takeaway boxes.
Smyth, 42, a protégé of Gordon Ramsay, said: “It’s been my dream to achieve this level but I never imagined it could happen … Core opened three years ago and it was my passion since I was 16-years-old.
"For the future, I hope young chefs – both male and female – have the chance to own a restaurant and achieve success. It’s an important message for now [given coronavirus].”
In 2018, Smyth was chosen to cater for Prince Harry and Meghan Markle’s wedding reception at Frogmore House, and is believed to have prepared an organic menu that included burgers with Wagyu beef and pork belly for guests.
Speaking of the honour at the time, Smyth, from Northern Ireland, said: “It couldn't have been more perfect... it was completely surreal. They [the Duke and Duchess] were involved in the menu, it was very important to them... it's a once in a lifetime thing so it's nice to be a part in it.”
Despite a very tough year for hospitality - with restaurants across the UK forced to close due to coronavirus - Monday’s event marked a significant point for UK restaurants, according to Gwendal Poullennec, the international director of Michelin guides.
He said: “Despite a challenging year our inspectors were glad to find new talents emerging everywhere in Great Britain and Ireland. To have two new three-star restaurants is a historic moment.”
With only 130 restaurants across the globe currently holding the coveted three Michelin star rating, Poullennec added that those who achieved the highest award were the “crème de la crème of the world of gastronomy”.
For 2021, the Michelin guide also awarded green stars to restaurants that endeavored to be kinder to the environment, including Angela’s in Margate, the Black Swan in Oldstead and Hypha in Chester.