Dan Barber is a chef on a mission: to change the way we eat not only when we're at restaurants, but when we're at home, too. The success of his restaurants Blue Hill, in Manhattan, and Blue Hill at Stone Barns, in the Hudson Valley a few miles upstate – the latter in the World's 50 Best – is testament to his unwavering commitment to this philosophy. He's a man whose career has shown the potential of top restaurateurs to effect genuine change in the global food system.

We caught up with him to get to grips with the concept of whole-farm dining, and how he uses his restaurants to teach the value of ethical, sustainable agriculture.

Have you seen more chefs realising the benefits of talking about a traceable supply chain and a connection to farms?

From my experience, I've always seen that the best chefs, whether they're in England or Paris or America or South America, are driven by a connection to a farm. Some more than others, but that has to do more with geography than philosophy. I've never met a chef who doesn't feel like the connection to a farm or many farms is not the backbone of his or her restaurant. I only know of some that don't talk about it at all, or where it gets overshadowed by something they're doing with their cuisine or their technique.

Dan Barber in the kitchen at restaurant Blue Hill at Stone Barns

Dan Barber in the kitchen at his acclaimed restaurant Blue Hill at Stone Barns

It's become increasingly important because the press has written about it more, and there are more opportunities for those connections to be made. There are more farmers' markets, for example; there's more access, which is driving more small farmers into the business; there's more outreach, and so those connections are made much easier than they used to be. I've seen chefs focus on it more; advertise it more on their menus; talk about it more – but that's where the culture is, and it's good for business.

Does your approach differ between Blue Hill and Blue Hill at Stone Barns? Does the latter benefit from being right on the farm?

I've noticed the difference. The challenges are more [in Manhattan], but I've also noticed the opportunities are there to do the exact same thing as we're doing here [at Blue Hill at Stone Barns]. And we're all hungry for these stories, and these connections – this is to the advantage of chefs, which is why we find more of them talking about it. There are so many differences, but mainly the experience is very different in New York. It's just a different vibe; it's quite energetic; it's a very small room. It's a faster pace at Blue Hill at Stone Barns – we've got 38 cooks here, whereas we've got five in New York. Same ingredients, same philosophy, interpreted very differently.

Blue Hill at Stone Barns explores organic, sustainable produce through both the restaurant and the educational centre. Do you think both are essential to changing people’s outlook on produce? Are restaurants alone enough?

You're talking to a guy who wears a chef's coat, so I think the experience of eating this kind of food at the right table, in the right circumstance, is just a very powerful educational experience. But that's not to say that being attached to a farm education centre doesn't help the cause, because there are a lot of ways into this issue. A more formalised education is great, and it's another opportunity to reach people.

A lot of people can't afford the kind of meal that we're talking about, too, so there's the access point of view – but I could have you come to Stone Barns Center, take a walk around the property, take a free educational class, have a sandwich and a soup for lunch, tour the farm formally afterwards, do a cooking class in the afternoon, sit down for dinner, and I could do that for cheaper than a weekend at Disneyland. But we try and look at the experience of dining here partly as an educational experience, without lecturing. And it's a gateway for many people.

A delicious plate of food is inexorably tied to great ecological stewardship; they're one and the same thing

Is it easier to convert diners to the farm-to-table concept with a rural restaurant than one in a city?

I think when diners are [at Blue Hill at Stone Barns] it's easier. But I also term that as a challenge – or an opportunity – for urban restaurants that are increasingly focused on advertising their connections to farms. This is a nice way to think about the future of restaurants, and the future of sustainability: as the world continues to become urbanised, there is a way to connect with the natural world, and a great way to do that is through a plate of food. And a good plate of food – a delicious plate of food – and the idea of deliciousness is inexorably tied to great ecological stewardship; they're one and the same thing.

To be sitting in midtown Manhattan and having a jawdroppingly delicious carrot is to connect yourself with great environmental stewardship, because you can't have a jawdroppingly delicious carrot without good stewardship; you can't have it without a good seed; you can't have it without good soil; you can't have it with a good farmer who's not making the right crop rotations; you can't have it with a farmer who's picking it at the wrong moment; you can't have it with a farmer who's shipping it 3,000 miles away.

All of those things and more conspire to argue that truly great flavour and good ecology are one and the same thing. That's an important thing for the increasingly urban populations to celebrate and recognise – that we have a power through our food choices to affect the way the world is used just outside the cityscape. It's easier for us to make those connections when your table is surrounded by farmland, definitely, but that's not to say that we can't do very much the same thing in the middle of a bustling city like London.

Catch Dan cooking on the rooftop at Selfridges at his wastED London pop-up, which runs from 24 February-2 April. For more info or to reserve places, go to selfridges.com/wastedlondon. For more info on Dan and his restaurants, visit bluehillfarm.com