Anthony Joshua helps himself to another sizable hunk of rib eye and follows it up with a pile of sautéed potatoes.

This media lunch, laid on by his promoter Eddie Hearn, has brought the 2012 Olympic gold medalist deep inside London’s Square Mile, to upmarket steakhouse Gaucho.

‘If I had known there was going to be this much good food,’ he says with a smile, ‘I would’ve brought the family.’

One of the advantages of operating inside the heavyweight division is that there is no battle with the scales. You can weigh whatever you like.

Some other weight-making stars of Hearn’s stable have rocked up at these lunches and gazed longingly at the prime cuts only to produce a pre-packed Tupperware dish of chicken breast and couscous. Not Joshua.

Of course, it also means that Joshua’s promising career could be scythed down at any moment by a man as big as, or even bigger than, his hulking 6ft 6in frame. As the old adage goes: ‘There is boxing, and then there is heavyweight boxing.’

His stature also means that this brand new heavy, who has knocked out all 14 of his professional opponents within three rounds, is open to the most extreme hyperbole that this sport can generate.

Some have said Joshua can go on to become the greatest boxer Great Britain has ever produced, some have even likened him to Muhammad Ali. Others have said he’s little more than a ‘hype job’, a body builder who is yet to take a punch on the chin, a bloke who will crumble as soon as somebody lands on that marketable face of his.

Joshua couldn’t care less: ‘Let’s just wait and see. People are going to like you or hate you whatever you do. I don’t focus on them.”

Like Ali, 26-year-old Joshua ended his amateur career by winning the Olympic gold medal and the 26-year-old is fully focused on his dream of one day ruling the heavyweight division as a professional too. But he also wants to follow in Ali’s footsteps in another way – by taking what is known in the trade as ‘big-time boxing’ all the way to Africa.

‘It’s where my parents are from, I spent some school time there in Nigeria and I go back and visit when I can as well. It’s a beautiful place that’s on the rise.’

2014 brought up 40 years since the ‘Rumble in the Jungle’, when Ali and George Foreman tangled in one of the greatest fights in the sport’s storied history.

The contest, which Ali won via eighth round stoppage using his fabled ‘rope-a-dope’ tactics, took place at the 20th of May Stadium in Kinshasa, Zaire, the country now known as the Democratic Republic of the Congo. For Joshua, an avid viewer of old boxing videos, it is one of his favourites.

And now AJ, full name Anthony Oluwafemi Olaseni Joshua – or Femi to his close friends and family, whose mother and father are both Nigerian, would love the chance to showcase his skills on the continent.

‘It’s where my parents are from, I spent some school time there in Nigeria and I go back and visit when I can as well. It’s a beautiful place that’s on the rise.

‘There are a lot of successful people coming out of the place and there are a lot of people struggling as well.

‘It’s a massive, massive, massive place so you’ve got both ends of both worlds. That’s where my parents are from; that’s my descent so I’m a very cultural person in that sense.’

Tattooed on his right deltoid beneath the word ‘wisdom’ is the outline of Africa, with a second line around Nigeria. ‘I got that tattoo done when I was younger,’ he says, patting the shoulder in question. ‘Now it means that with every punch, I’m putting mother Africa in their jaw. I like that.’

And, when asked whether he would like the chance to feature in a Rumble in the Jungle of his own, the 26-year-old added: ‘When you think about stuff like that – why wouldn’t I want to recreate that? That’s unbelievable.

‘A lot of people go to Vegas and see that as the pinnacle for boxing but I feel that I’d love to box in Africa because of what Ali did.

‘It’s history, man, that’s unbelievable I think – it makes a lot of sense.’

But, for the moment, what makes sense lies a little closer to home. A 2009 amateur defeat to Dillian Whyte has paved the way for a rematch now both men are operating within the paid ranks.

Anthony Joshua and Dillian Whyte (nice suit) pose for a photo with promoter Eddie Hearn © Getty Images

It has been a bitter build-up between Joshua, of Watford, and his London rival Whyte, a Jamaican now living in Brixton, who is currently 16-0. Whyte has called his opponent a ‘scumbag’ and accused Joshua, the articulate, media-friendly giant, of being ‘fake’, of applying a persona when the cameras are on. Joshua says Whyte is not in his league.

‘He shouldn’t talk like that,’ Joshua says, his smile vanishing. ‘What gives him the right to talk like that?

‘I don’t think he has done anything. I think everyone is entitled to an opinion. We will go to war. I told him ‘three months after this fight no one will remember you’. Let him throw mud and talk – I will fight.’

The clash, at the 02 Arena on December 12, is for the British and Commonwealth titles but both men harbour hopes of one day claiming world belts.

Joshua thinks he could even dethrone the new king, and fulfil his dream.

And they will have been encouraged by the seismic shift in heavyweight boxing, when Tyson Fury beat long-term heavyweight icon Wladimir Klitschko in Dusseldorf, which meant the WBO, WBA and IBF titles have returned to Britain.

Fury’s victory signalled a changing time in the heavyweight division and Joshua thinks he could even dethrone the new king, and fulfil his dream, as early as next year.

He said: ‘Fury has been pro for eight years, I’ve been a pro for two. I’d fight for that belt 100 per cent. I’ve got to fight for the British belt but I’d fight for that world belt 100 per cent even if it was next year.

Anthony Joshua knocks out Raphael Zumbano Love during the Heavyweight Contest during Resurrection Fight Night at Barclaycard Arena on May 9, 2015 in Birmingham, England. © Getty Images
© Getty Images

‘People demanded the Whyte fight so we made it because people wanted to see it. People have wanted to see me and Fury fight, title or no title; people want to see it anyway. That’s why I think that fight will be made.

‘Even though I am not at that level and haven’t fought any contenders, that fight will be fast-tracked because people want to see us get it on. I think it will be sooner rather than later.’

All food for thought for next year. For now, he’s got enough on his plate.