The prime thing he wants to get across today is how important his new World War II adventure film, Inglourious Basterds is to him. Initially he demonstrates uncharacteristic humility, when I ask if this is his magnum opus.
"I'm not trying to be cagey, but it's not really for the chicken to speak of his own soup," he replies in his highly entertaining vernacular. "That's more for you to decide."
The writer-director of films including Reservoir Dogs, Pulp Fiction and Kill Bill Volume 1 and Volume 2, says the most important thing for him is maintaining a high standard in his filmography.
"I've studied directors' careers and most of them do not get better as they get older. I don't want some kid coming into a video store and picking the movie I did for hire, or the one I did to pay for my pool. I want all of my movies to be strong, but I also want them to have the youthful energy that Reservoir Dogs had. It can have maturity inside but I don't need to prove that any more. I've done that already with Jackie Brown. My third movie already had a maturity to it, all right? It's not something I have to grow into. Basically I don't like those old man movies."
Of course Jackie Brown, possibly Tarantino's most straightforward venture, was based on a novel by Elmore Leonard, so doesn't naturally sit happily among Tarantino's other works.
"The maturity of Jackie Brown doesn't make it better than the comic book pyrotechnics of Kill Bill: Volume 1," he argues, "it makes it different. Oddly enough Kill Bill was more personal to me because I wrote it. Part of my thing is to parallel my real life somehow and to disguise it inside a genre. It's not my job to tell you the details, though," he sniggers.
Knowing that his head was on the chopping block following the failure of Grindhouse, an intriguing concept combining the old drive-in experience and a modern movie (only the first half, Death Proof, was released here, while Robert Rodriguez's Planet Terror went straight to DVD), Tarantino was aware he had to come up with the goods in Inglourious Basterds.
"I wanted to work with a big actor because I needed a big opening," he concedes of casting Brad Pitt. Yet he insists he wouldn't have cast Pitt if he wasn't the right actor for the role.
"Literally it was one of those situations where as I was writing the script I was thinking, 'Brad could be good in this'. I wrote a little bit more, 'Hey, Brad could be [expletive] awesome in this! Right, now I need Brad, but I'm [expletive] because he's a little hard to get hold of because he's in the south of France. I'd met him a few times but I didn't really know him."
Tarantino managed to contact Pitt as he had the same agent as his good friend Uma Thurman. Still, he was worried.
"I know that when Brad makes a movie Angelina doesn't make a a movie so he may not have been available. Not only was I trying to get the most sought after movie star in the world, I was saying, 'I've gotta go now!' I couldn't wait for him. Sometimes the movie gods smile on you," Tarantino grins.
Since Inglourious premiered in Cannes in May, Tarantino has re-edited the film. Its success or failure could make or break the film's beleaguered financiers, The Weinstein Company, who have long supported Tarantino's talent. Still, for some, the film's subtitling may also be a problem as 70pc of the film is in French and German. But Tarantino wasn't going to budge on that.
Certainly the one-time wunderkind has many more films to make. However, he has said in previous interviews he wants to retire at 60, to write and be a kind of Mark Twain.
"I do intend to stop directing at 60 -- unless my last film is a fiasco. I may have to go to 62 to redeem myself," he laughs. "I feel like I can be a novelist and that's a gift I intend to give myself. I don't want to have to be worrying about schedules and timing when I'm older."
Inglourious Basterds opens in cinemas on August 21