Mark Moriarty started cooking during his summer holidays aged 15 at the Chart House restaurant in Dingle, Co Kerry, Ireland. While completing his degree in Culinary Arts at Dublin Institute of Technology he began working under Kevin Thornton at Thorntons Restaurant for two years. In 2012 he moved to The Greenhouse on Dawson St in Dublin and began working with Mickael Viljanen.

In 2013 he was named the Euro Toques Irish Young Chef of the Year at a ceremony at Google HQ in Dublin. After completing his degree in 2014 he set up the Culinary Counter, delivering pop up restaurants around Ireland alongside chef Ciaran Sweeney.

In February 2015 he was crowned the San Pellegrino UK & Ireland Young chef of the Year at a ceremony in Harrods, London. Representing this region, and mentored by Michelin starred Clare Smyth MBE, Mark went on to be crowned the San Pellegrino World Young Chef of the Year at a ceremony in Milan, Italy. He won by presenting his signature dish of 'Celeriac baked in barley and fermented hay, cured and smoked celeriac, toasted hay tea' to an esteemed jury including Massimo Bottura, Grant Achatz, Yannick Allenno and Joan Roca.

Mark took his Irish cooking around the world in 2016, bringing his pop up restaurant on tour. He cooked in Milan, Alta Badia, Melbourne, Charleston, Paris, Singapore, Amalfi, Moscow, London, Cape Town, Johannesburg, Hong Kong and finally Dublin before handing over the title in October, 2016

Since then he has been listed on the Forbes magazine 30 under 30 for innovation in the arts sector. In January 2017, Mark moved to Melbourne, Australia and worked with Andrew McConnell at Cutler&Co restaurant. Mark was a speaker at the 2017 Worlds 50 Best Restaurants ceremony and has worked on projects with Peroni and Bord Bia; the Irish food board.

Mark remained part of the team at The Greenhouse Restaurant on Dawson Street in Dublin, which won its second Michelin star in October 2019. Here he worked alongside head chef Mickael Viljanen and the small kitchen brigade, before finishing in May 2021.

In 2018 Mark was also brought into the team at Diageo plc, as their 'Chef in Residence. Here he consults on food and flavour across their reserve brands, including Johnnie Walker whisky, Tanqueray gin and Ketel One Vodka, as well as internal team training. He works closely with the team at M&S Ireland as a Brand Ambassador

In September 2019, his debut series ‘Beyond the Menu’ aired on RTE One, the most watched channel in Ireland. The series saw Mark giving a unique insight into the restaurant industry in Ireland, through meeting, and hosting pop up restaurants with 6 of the countries best young chefs. The series ran for 2 seasons. In May 2020, his second series ‘Cook In’ began on the same channel, in response to the Covid pandemic

Since 2021 ‘Mark Moriarty:Off Duty Chef’ has been a hit on Irish screens after 2 seasons. In 2023, Mark released his first cookery book ‘Flavour’ published by Gill

Mark is also a regular contributor to RTE’s Today show and BBC’s Saturday Kitchen.