Dan Churchill has just cooked dinner for an élite alpine ski racer. “She’s chasing her final world championship,” he says over the phone from Åre, Sweden. “I’m here to make sure that breakfast, lunch, snacks and dinner are optimised for her performance and recovery.” No pressure.

At the dinner table is American three time Olympic medallist Lindsey Vonn. Churchill, a former fitness coach who caught the public eye in the 2013 season of MasterChef Australia, has cooked for Vonn all over the world, including at last year’s Pyeongchang Winter Olympics.

But Churchill grew up a long way from snow-covered slopes. He was born on Sydney’s northern beaches with “sand in his nappy”, he laughs, and spent his early teens surfing and devotedly cooking Jamie Oliver recipes. Before his megawatt 23-year-old smile had a chance to melt hearts on television, he’d done a Masters in Exercise Science and had already published his first cookbook. There were another two books after that, before he relocated in 2015 to New York City, a man on a mission.

“As a chef in this new millennial age with social media, there’s action points,” he says. “It wasn’t just like, oh I’ll have a crack. To change the world through food you have to have a voice, you have to have an outlet, you have to have a reach.”

‘Changing the World Through Food’, as his email signature states, is no small task but one he’s confident he can gauge.

“When I teach someone how to cook right and eat right, they then want to train right,” he says. His food philosophy is pretty simple. “I call it easy, colourful cooking. It’s like Instagram’s Explorer page. What ultimately attracts your eye are the things with the most colour.”

At Charley St, the café he opened last year in Manhattan’s NoLita district – “so I can get a decent cup of Proud Mary coffee every day for the rest of my life” – that colour-code approach equates to a menu of toasts topped with the likes of coconut-beet spread, apple slaw and whipped goat’s cheese, and bowls, perhaps shakshuka with spicy chickpeas and pesto.

Cooking for an athlete like Vonn, meanwhile, might mean roast chicken, “the juices saved for an epic three-grain salad”, or on race day PB&J oatmeal. “I don’t talk about health as six per cent body fat and just having steamed chicken and broccoli,” says Churchill. “Colourful food promotes the release of serotonin, and that leaves you feeling inspired to hit the gym or go for a run the next day.”

The 29-year-old wasn’t keen to open a 200-seat restaurant that required him to be there every minute of the day, and so the fast-casual concept of Charley St was born. He sees it as a scalable concept and he intends to open more elsewhere. “I want to have the ability to build kitchens in Third World countries,” he says. “I could have 100 Charley Sts in different parts of the world. It has a core message that can go places.”

It’s already going straight to Instagram, thanks to designer Liza Kuhn and her avocado-print wallpaper in the bathroom. The whole café, in fact, makes a compelling case for #nofilter. Churchill is well aware of the role social media can play in telling a brand’s story and he knows how to hashtag hustle. For that very reason, they’ve built a studio kitchen in the basement and shared the process step-by-step on his channels. It will be used for creating original content as well as staff workshops on seasonality for instance, and hosting high-intensity workouts with post-sweat-session jars of almond-milk chia.

As well as responding direct to his 60,000-plus Instagram followers, Churchill is a regular on Good Morning America, caters dinner parties for Naomi Watts and was recruited to provide nutrition advice and recipes for Centr, a new fitness platform from Chris Hemsworth that launched this month. Perhaps his biggest achievement yet, however, came late last year when he was listed in the 2019 Food & Beverage category of Forbes ’ 30 Under 30. The first thing he did? “I walked into Charley St, and whether it was the person who does the dishes or the barista, I went around to every single member of my team and congratulated them. They’re a big part of this, too.”

While others might prefer to distance themselves from their reality TV beginnings, Churchill says he’s “forever grateful” for his time on MasterChef, and later his hosting gig on Surfing the Menu: The Next Generation with delicious. contributor Hayden Quinn. “I learnt about camera angles, how to deal with different members of a production team. I look at it as the biggest crash-course in food possible.” These days he looks to people such as chef Dan Barber, of New York’s Blue Hill at Stone Barns, for inspiration on sustainability and agriculture, and Tesla CEO, Elon Musk, for his “farfetched ideas and ability to think outside the box in business”.

With the recognition from Forbes and a namecheck by The New York Times in Charley St’s first six months, 2019 is looking colourful, all right. “I could’ve stayed in Australia doing what I was doing and I’m sure I would’ve loved it and surfed every day,” he says. “But in New York, people constantly throw you ideas and opportunities. And you’re nothing but excited to be a part of them.”