Michelin also announced 21 new one-star restaurants, including six in the capital, at a ceremony held at London's Imax in Waterloo.
New one-star restaurants to make it into the red book include Tomos Parry's Brat in Shoreditch, Ikoyi in St James's, Sabor in Westminster and Hide in Mayfair.
Outside of the capital one stars were awarded to restaurants including Rogan & Co in Cartmel, Gidleigh Park in Devon, Sorrel in Dorking,The Fordwich Arms in Fordwich, Salt in Stratford-Upon-Avon and Tim Allen's The Flitch of Bacon.
Three Irish restaurants have also been given a new one-star rating - Mews in Baltimore, Ichigo Ichie in Cork and Chesnut in Ballydehob.
On receiving the award, presented to her by her mentor Gordon Ramsay, Smyth said: "It is even more special Gordon handing it to me."
Speaking after receiving his restaurant's award, James Knappett, chef-patron at Kitchen Table said it felt "beyond amazing".
"It makes your career worth everything. I always said if I keep my head down my work will be recognised one day, and today's the day."
"I knew it would come because I was working for it, and whether it was this year, the next year or the year after, I knew I'd get it eventually because I surround myself with great people, my team and my wife. I have ambitions and I won't stop until I get them."
There were no new three Michelin stars awarded in the 2019 guide.
Gwendal Poullennec, international director for The Michelin Guide, said the guide was more relevant than ever before.
“In a world dominated by user reviews, professional recommendations have never been so relevant. You need a reference you can trust and make a booking safe in the knowledge you will get the best quality food and service, this is what the Michelin Guide delivers."
Also speaking at the event, Pascal Couasnon, The Michelin Guide food and travel managing director, said the guide would continue to innovate.
“The Michelin Guide will continue to promote high quality food, be closer to diners, innovate and continue to be a worldwide reference for diners," he said.
New two Michelin-starred restaurants
Core by Clare Smyth, Notting Hill
Moor Hall, Aughton
Kitchen Table & Bubbledogs, Fitzrovia
New one Michelin starred restaurants
Ikoyi, St James's
Rogan & Co, Cartmel
Gidleigh Park, Chagford
Tim Allen's Flitch of Bacon, Little Dunmow
Olive Tree, Bath
Winteringham Fields, Winteringham
Oxford Kitchen, Oxford
Fordwich Arms, Fordwich
White Swan, Fence
Ichigo Ichie, Cork