Cooking up a storm in New York

• Scott Campbell at work in the kitchen of his New Leaf restaurant

Scott Campbell, an impressively tall, sandy-haired 48-year-old, is executive chef at one of New York's finest restaurants and bars, the New Leaf, in lovely, leafy Fort Tryon Park, at the tip of northern Manhattan.

And – Campbell's undoubted talents aside – it's all thanks to Midler and her crusading zeal for all things green, which naturally includes his cuisine featuring the freshest of locally-grown, seasonal ingredients, such as his Hudson Valley corn soup and lavender crusted mahi mahi.

Sixty-four-year-old Midler may have been one of the most outrageous stars of her day, but the self-proclaimed "Queen of Trash" – in every sense, since she founded the New York Restoration Project (NYRP), which has transformed the city, especially its once-notorious, garbage-strewn, sinister parks – is keen to spread the message about the only restaurant in the city where you can literally dine out in the middle of a forest, where bald eagles and falcons fly.

When I interviewed Midler for the 2011 Louis Vuitton City Guide to New York, which is published on 15 October, she told me I had to meet Scott Campbell. "He's a Celt, you know," she told me in that distinctive sexy purr, with which she's entertained us for more than four decades, not only with her music, but comedy and films – Midler has four Golden Globes, three Emmys, three Grammys and a Tony. And her commitment to New York City is truly impressive.

Under her leadership, the NYRP has restored and helped maintain six city parks, removed 1,905 tons of rubbish from green spaces, saved 114 community gardens, and in partnership with the city and Mayor Bloomberg plans to plant a million trees throughout the five boroughs by 2017.

Midler moved back there from Los Angeles in 1994 and was appalled to discover litter-clogged streets and filthy, dangerous parks, so a year later she founded the NYRP. She'd already pulled on a pair of gloves and got out there herself, repeating her mantra, "Get the trash off the streets and onto the stage where it belongs!"

After cleaning up an Upper Manhattan park in Fort Washington that nobody ever went to – "well, only to dump dead bodies" – the NYRP embarked on Fort Tryon Park, home to The Cloisters museum, dedicated to man-made artefacts from the Middle Ages, and its gardens. In the park, Midler and her team stumbled upon a dilapidated 1930s building, which was transformed in 2001 into a cafe – it's since been rechristened New Leaf Bar & Restaurant.

"And that's where I came in, in 2007," says Campbell, whose crisp whites are pristine, despite the fact he has just prepared Midler's buffet. She's such a trouper she's doing a photoshoot for Conde Nast Traveller, despite having a cold. "I don't want to infect you," she declares, rubbing elbows rather than shaking hands with me and air-kissing Campbell.

"Boy, can my friend Scott cook!" she exclaims, licking her lips before heading back to the buffet.

Born and raised in Grosse Point, Michigan – Clint Eastwood's 2008 movie, Gran Torino was filmed on the block where he grew up – Campbell's heart belongs to New York. However, his late father, Richard, passed on his enormous pride in the family's Scottish roots and their clan to his three children. Campbell began his career in Detroit at the London Chop House, before becoming sous-chef at the legendary Oak Room in New York's Plaza Hotel.

"This city is the culinary capital of the world. I love working here," he says in his Midwest drawl, sighing over his Michigan accent. "I'd love to have a Scottish brogue."

None of the kitchens in which he's cooked, Campbell points out, can begin to compete with the idyllic sylvan setting of the New Leaf. "With The Cloisters just a short walk away, it's a truly inspiring place – the rugged, unspoilt landscape is probably rather like Scotland. Indeed, we even have Heather Gardens. How Scottish is that?" He grins, settling down to talk outside the main dining room, with its massive, oak-trussed high ceiling, while Midler prepares for yet another change of outfit and just one more close-up.

Despite growing up as an all-American boy, Campbell says he was never in any doubt that his roots were in Scotland, which he's visited several time while carving out a career in some of Manhattan's most legendary establishments, from Union Square Cafe to Le Cirque and Windows on the World at the World Trade Center, some time before the tragic events of 9/11.

"My dad talked a lot about how the Campbells emigrated to the States from the Highlands of Scotland during the potato famine in the 1840s. Since he died, I feel there are huge gaps in my sense of Scottish history; I have to remedy that one of these days. When I was clearing up his things when he passed away, I found all these hand-written family letters from the late 1800s, which are real interesting.

"They are so fragile I was almost afraid to open them up. Being a pop historian – I'm really into history – nonetheless, I felt I should leave them alone and let someone who has real background knowledge of the period investigate them. I sure treasure them, but for the time being I'm leaving them archived until I maybe ask a museum to look at them," he says.

His father, who was president of the St Andrew's Society of Detroit, began his career in the motor trade but ended up selling computers for IBM. "He was a great salesman. He had a good mouth – he was a good Scotsman in that sense," laughs Campbell, adding that he and his siblings were inevitably given Scottish names. "Obviously, I'm Scott, my brother's Blair and my sister's called Heather. That was so interesting to me when I first started at the New Leaf, with its amazing Heather Gardens. For long enough I thought they'd named them for a woman benefactor. I didn't realise that it was such a sturdy plant that it grows 12 months out of the year, even under a foot of snow."

When Campbell first visited Scotland a few years ago, his father insisted he follow the Robert Burns trail. "I also went to Glasgow, which I loved, especially the venison, with raisins soaked in Scotch, at The Buttery restaurant. Edinburgh has to be the most beautiful city I've ever seen, despite the haggis. Now I know why they put so much mustard on it. But, the city's sublime – those gardens beneath the Castle. Wow!

"Being a good New Yorker I walked the streets. So gorgeous! And I rented a car another time I visited. I drove to Aberdeen and on the way I saw so many emerald-green fields. I also discovered why everyone in Scotland drinks Scotch in the middle of July. It's real damp! I've yet to explore the Highlands, which I'll definitely do since that's where we're from originally."

So, says Campbell, like his father before him he has a passion for Scotland and most things Scottish. "But not to the extent that I'll be serving haggis in the New Leaf. I ate so much of it when I was last there all I'll say is I know now why it gets such a bad rap."

What does he think of Gordon Ramsay? "I really wanted to try his food, with him being a Scot and all, and from Glasgow," Campbell replies. "I made a reservation at his three-Michelin starred restaurant, in London, right before 9/11.

"They asked me to call back a couple of days ahead of the reservation, but when I did I was told I'd never made the booking. I said to them, 'Look, I've worked at Le Cirque, I've cooked with Daniel (Boulud, an award-laden New York chef], and at very prestigious restaurants, so I know how to make a reservation. They just said, 'Well, you don't have one.'

"I believe in gentlemanly values, so I was really surprised at their inhospitable way of treating diners, but I guess after watching Ramsay on TV, I was like, 'OK, I guess he doesn't need my money.'

"Speaking of a Scot who is very impressive, though, how about Charles Rennie Mackintosh? If I could do with food, the beautiful things he did with design and architecture, I'd be real happy. Brilliant! He blows me away." A keen amateur artist, Campbell insists he grew up in "the Dark Ages of American cuisine – everything came out of a can or a packet".

He was in his early twenties when he first moved to New York, where he won a reputation for off-menu specialities: a line in organic baby food – although he and his environmentalist wife, Linda, to whom he's been married for 20 years, have no children themselves – and his secret-recipe, wickedly rich Valrhona hot chocolate. "Culinarily, in the early 1990s New York food was very French, but now it's a real kaleidoscope of different types of cuisine. I incorporate elements of Asia, the Mediterranean, classic French flavours and Californian cuisine into all my menus. Scottish influences? I sure serve a lot of delicious salmon – today it's pan-seared, with organic mixed greens, grapefruit segments and lemon vinaigrette."

He often thinks about his dad when he creates inventive new dishes "Like all good Scotsmen, he liked to eat way too much."