You don't really interview Charlie Trotter. You pose a question to Chicago's most famed chef and wait to see where he goes. And goes. And goes.

Ask him why he never repeats a menu – one New Yorker who's dined here over 400 times has never savoured the same meal - and Trotter invokes icons of jazz and folk.

"The two biggest musical influences to me are Miles Davis and Bob Dylan, artists that really never played anything the same way twice," the self-described philosopher-chef told me in the longest, frankest and most wide-ranging interview I've done in months. "That's kind of our style."

Ask him why he banned foie gras (cruel) and smoking (annoying to other guests) at Charlie Trotter's before the city of Chicago did, and he'll lament the nanny state.

"By all means allow smoking," he said over a dry, quenching chardonnay.

"It's up to you. It's up to the proprietor of the business. It's up to the clients to determine if they want smoking or not have smoking. We can't get our grubby government hands into everything."

Big questions

So perhaps it's no surprise he's closing his lucrative bistro – and bidding farewell to around 200 guests a night paying $150 to $200 apiece even before they order from a wine menu that fills three cellars – to study philosophy.

Trotter says he wants to explore the big questions: "What is the good. What is the right ... And then the most important thing of all: the God question. Who created the universe and the cosmos, and if it was God, who created God?"

He's narrowed the site of his future academic home to two: the University of Chicago and Northwestern University (When I told him Northwestern is my alma mater he scolded me for failing to come to plunk down what was then a week's living allowance on a pricey meal at Chicago's famed haven of white-napkin dining.)

He's as gracious to his patrons, charming each table, as he was to the Al Jazeera team that invaded both his studio and working kitchens (producer Tom Szypulski, photographer Cyril Dowlatshahi and me).

He ladled out several courses of the evening's mouth-watering menu – centered around free range, hormone-free, antibiotic free meats - each paired with a sommelier's choice of wine, before calling us freeloaders and asking when we were leaving (There might have been a wink in there).

Draconian boss

Trotter pairs deadpan humour ("If it weren't for the customers and it weren't for the employees, the restaurant business would be the greatest business in the world") with frank libertarian philosophy ("I'm in favour of legalising everything - gambling, drugs, prostitution") and a grudging generosity ("Get this man a double. He's got a long drive ahead of him.")

He's also notoriously demanding, voted one of Chicago's most draconian bosses.

After spending a day as a guest in Trotter's kitchen, Chicago gourmand Scott Warner says he told a pastry chef, "'You must love this.'" She looked up, straight faced, and said, "I have no life. I have no life!"

There's a scene in the Julia Roberts film My Best Friend's Wedding where Trotter, playing himself, tells a sous chef: "I'll kill your whole family if you don't get this right. I need this perfect!"

It might be a scene from a film, but you get the sense it's no act.

Trotter and his staff insist he's equally hard on himself. Perhaps that explains why, having transformed Chicago from a town known for pizza and polish sausages to a renowned international centre of haute cuisine, Charlie Trotter is moving on.