Suspense was the flavour on my tongue as I approached the London Hilton at Park Lane for a short interview with Pierre Hermé. I knew I would have to broach – and therefore answer to – the tongue-in-cheek blog post I’d composed in July as an open letter to the pastry legend.

During my visit by invitation to his London boutique I’d taken issue with his UK area manager dictating what I could and couldn’t photograph. My letter to Hermé concluded with a statement of acquiescence: all content for my website would henceforth be subject to his approval.

Had Hermé read the blog post? If so, had this rendezvous been arranged in response to it? All I knew was that Hermé had travelled to London from Paris for Valrhona Chocolate to help promote its new book, Cooking with Chocolate. Andre Dang, the ace food PR who’d arranged this brief meeting (but not the July visit to the boutique), had said nothing about the letter to me – nor had I, to him.

To play it safe I decided to interview a culinary genius in the art of saving the best for last by saving the worst for last. It’s an old journalist’s tactic: Pose the most difficult questions as the meeting is winding down. If the subject is offended and storms out you still have a story from the answers to the prior questions.

I was eager to learn about the creative process behind Hermé’s incomparable macaron flavours and signature combinations like olive oil & vanilla, violet & black currant and salted-butter-caramel & apple. How often, I asked, did new flavours in development end up on the cutting room floor? He answered with a shrug: Never.

“It’s a creation,” he said. “It’s not a process.”

Hermé tossed in lyrical French when discussing his oeuvre, describing, for example, flavour combinations not as associations or mariages of ingredients but rather as conversations des goûts – “conversations of tastes”. He nevertheless came across as an extremely serious, no-nonsense chef who reserved his puff and flash for pastries. Even if it did enter the back of my mind that he might have my letter in the back of his, Hermé’s matter-of-fact self-confidence could not be dismissed as posturing.

“When I imagine a new flavour I always have in my head a scenario de goûts,” he explained. “I write down the quantities before I do two tests.”

And what if a new scenario des goûts, to use his term for what most of us call a recipe, proved to be unpopular? Not his concern. Pastry, he scoffed, is not democratic.

His great challenge is identifying ingredients that meet his expectations. In his book a lemon is not just a lemon. The fruit can vary according to acidity, bitterness, juiciness, even the texture of the zest. Much like the perfumers at Guerlain and Rochas, the fragrance houses he’s worked with, Hermé must identify not just the main components of a formula but also the most suitable varieties of and sources for those ingredients. His recipe for the Infiniment Vanille (“Infinitely Vanilla”) macaron, featured in the recently released English edition of Pierre Hermé Macarons, calls for vanilla pods from Mexico, Madagascar and Tahiti. For this, the corollary to Guerlain’s Spiritueuse Double Vanille perfume, he desired a woody and floral vanilla with undertones of almond. He knew he couldn’t capture all that in only one type of vanilla pod.

Could so exacting a pastry chef sanction a scenario restricting the content, angle, composition and background of photographs taken of his macarons displayed in his boutiques? With his cappuccino cup nearly empty and the pages of my memo pad nearly full I at last posed a short version of that question. He was ready for it – yes, he’d read my open letter – but the words did not come easily.

“No, of course you can take photographs,” he replied, suggesting the behaviour of his UK area manager had been “maladroit”. That individual, he added, was no longer working at the boutique.

I didn’t like being responsible for anyone’s dismissal but I was happy with the interview. In 15 minutes I’d gotten more than I expected, plus the difficult business was behind us. In parting we discovered our mutual love for burgers. True burgers. I told Hermé about my BurgerMonday series of London pop-ups and my plans to organise one in Paris early in 2012. Lionel Lévy, a Marseille chef we both knew and admired, would be flipping the burgers. Hermé handed me his business card and said if invited he would be delighted to attend.

He was out the door and off to another rendezvous before I thought to warn him about the restrictions on photography at all my pop-ups: No one may take shots of the “young” behind young&foodish from a low angle. These give the false impression I have double chin.