Opera, chamber music, international stars and local wannabes, the annual St Jude’s Proms have it all. Running from June 25 to July 3 there are 17 concerts over nine days. With profits shared between two charities, Toynbee Hall and the North London Hospice, audiences can enjoy themselves and do good at the same time.

He wins enough awards to fill a bathroom shelf respectably. He ranks among the international elite, playing the grandest halls.

And while some new arrivals on the keyboard circuit draw the quiet contempt of more established colleagues (usually for showmanship and self-indulgence) you’re unlikely to hear anything but praise for the still seriously young Benjamin Grosvenor - who is all of 23 but probably the biggest name this year at the St Jude’s Proms.

Playing in recital with Korean violinist Hyeyoon Park, he is, as one of Britain’s other leading pianists Steven Osborne put it to me recently, “the real thing… genuine, transparent, honest, the outstanding fiigure of his generation.”

For the record, any list of Grosvenor’s attributes should also feature modesty and reticence – to a degree that make him hard to interview. He knows his own worth, but he doesn’t trumpet it.

“I’m not so shy now as I used to be”, he said when we last talked, “but you could say I’m introverted. I’ve got good friends, a supportive family.

“But I’m away so much I don’t see enough of them. It’s a lonely business, playing the piano, with a lot of hanging around in hotel rooms – although the internet and Skype make that more bearable. You can at least keep in touch with people”.

A particular concern has been to keep in touch with his roots.

When we met up, he was house-hunting; but until then he’d always lived with his parents and had an upbringing markedly different to that of the many wunderkind musicians who get processed into specialist schools and hothouse environments.

Born in 1992 in Westcliff , he went to local schools, and had his first experience of public performance playing in a seafront restaurant that served fish & chips.

But what began so unremarkably developed into something that his mother – who taught piano – recognised as special and beyond her competence.

Aged 9, he went off as a boarder to the specialist Menuhin School for promising musicians. But he only lasted a few days there before coming home. “It wasn’t right”, he says, ‘” I wasn’t happy there”.

Two years after the shortlived Menuhin experience, he won the piano section of the BBC Young Musician competition.

That he failed to win it overall was almost certainly because of his extreme youth (he lost out to the then 16 year-old violinist Nicola Benedetti), but the TV audience loved him and the offers rolled in.

At 13 he was playing concertos at the Albert Hall.

At 14 he was taken up for ‘development’ by EMI. And no, he says, he wasn’t overwhelmed by pressure.

“My parents were careful, controlling the engagements so there weren’t more than I could handle, and organising them in 3-month blocks so there wasn’t too much interference with school”.

He made a firm choice to avoid the major international competitions: he’s ambitious but not gladiatorial.

And he didn’t need to with a champion like the BBC, which nurtured his career, provided broadcast platforms, and absorbed him into its New Generation Artists scheme.

In 2011 – Grosvenor’s annus mirabilis – he became, at 19, the youngest ever artist to open the BBC Proms season (with Liszt’s 2nd Concerto); he featured again in the Proms, playing the Britten Concerto; he was signed by Decca (its first new British pianist in sixty years); and he issued his first CD on the label - a recital disc of Chopin, Liszt and Ravel that won two Gramophone Awards and a Classical Brit.

While all this was happening he was still a student at London’s Royal Academy – he only graduated in 2012 – and it was strange to visit him there, surrounded by contemporaries who were struggling to get lunchtime dates in local churches while he was playing in the glare of international attention.

A glare that intensified last year when he starred at the Last Night of the Proms, playing Shostakovich’s 2nd Concerto to a broadcast audience of millions worldwide.

What impressed then, as invariably with his playing, was a combination of youthful freshness and mature musicality that comes over as uncalculated, unaffected.

There’s no posturing, no antics, nothing in the way - and yet the personality is unmistakeable.

“I never want to hear people praise a performance as just about the music’, he says, “because it’s not: the player is there too, and part of it. You don’t set out intending to be different at all costs, but what the composer puts on the page isn’t the last word. The pianist Jorge Bolet said that composers might live with a piece for months as they write it, but performers live with it for a lifetime and discover things the author never realised were there. I think that’s true”.

So far, the process of discovery for Grosvenor has been crazily accelerated.

Rising young musicians have to learn a lot of repertory at speed to fill their concerts. And it’s noticeable that although the benchmark Austro-German classics – Mozart through to Brahms – do turn up in his playing schedule, it’s on other, less ‘core’ music that he’s built his reputation.

His recital programmes have an idiosyncratic eloquence – as you’ll find in the violin & piano repertoire he’s bring to St Jude’s with Hyeyoon Park. OK, there are two standard Beethoven and Brahms sonatas.

But there’s also Poulenc and Ravel. And since his early days, the latter of those two composers has, above all others, been his speciality.

It was with Ravel that he competed for the BBC Young Musician prize, and made his adolescent Carnegie Hall debut. The composer’s music features on his first two Decca CDs.

And he plays it with exemplary finesse, acknowledging the silent scream of pain that lies contained by the perfection of its formal packaging.

As for the Viennese classics, he’s proceeding cautiously through Mozart, Beethoven and Brahms, biding his time.

Which is a good idea.

To have achieved so much at 23 begs questions about what you’ll do during the next half century. A risk with long careers is that eventually you look back with embarrassment on what you did, so publicly, when young. But that’s not something Grosvenor needs to worry about yet.

Benjamin Grosvenor and Hyeyoon Park, June 28, 7.45pm, St Jude’s Church.