Lee Hatch didn't let that dissuade her. She and her husband were visiting Manhattan from Sydney, Australia, where they'd first hear about the cronut.

"This is our third attempt of lining up here," Hatch says. "And we thought, well, we're on holiday, we're here for a month, so we'll give it a go if it's the last thing we do before we go home."

Ansel worked on the recipe for two months, trying to perfect a dough that would hold up in the fryer and could be filled with cream, without becoming too soft.

He finally hit on a winning recipe, "something that people have not seen before," he says. "It's something that has a doughnut shape, it's flaky like a croissant, and that's why it's called a 'cronut.' "

So why has it caught on?

Irma Zandl is president of the consumer trends company Zandl Group. "There are parts of the brain that become super active when a fad idea is heard, and people want to pass it on," she says.

Then there is the nostalgia factor.

Allison Carruth is author of the new book, Global Appetites: American Power and the Literature in Food. She says Americans get wrapped up in foods that are tied up with a longing, "for the stuff of childhood and the stuff of our past, or at least our imagined past."

You can trace food trends back to the Renaissance, she says, when chocolate and spices took off. And in a way, it's not complicated: We like things that taste good.

"There is a kind of fundamental and even primal impulse in the human brain for food to also be pleasurable and to be communal and shared and delicious," Carruth says.

But a big difference between the Renaissance and today? Technology.

"One of the things that we've seen with the advent of all these blogs and social media is that people's desire to be tapped in and to be perceived to be somebody who is in the know is much greater," Zandl says.

The New York Magazine food blog Grub Street wrote about the cronut when Ansel first made them.

"And on the same night," Ansel says, "they called us and told us that their traffic on the website increased 300 percent, and they had over 140,000 links to the website."

It was then, Ansel says, he knew he had a hit. And the long lines outside the bakery are, in fact, part of it.

"The waiting itself is a huge part of the pleasure," Carruth says. "Not only because we feel we're participating in something that's fashionable or trendy, but because we're sort of signalling that we value a certain kind of experience."

And for those who can't make it to New York City to wait in a line, imitations have sprung up all over.

Ansel has trademarked the name "cronut," but in Washington, D.C., you can buy a doissant; in Vancouver, a frissant; and in the Philippines, Dunkin' Donuts has introduced the Donut Croissant. A Dunkin' Donuts spokesman says they have no plans to sell it in the United States at this time.

So how long can the cronut buzz last? As with everything else, there is a shelf life.

"We can only sustain so long one product, one brand, one entrepreneur having the spotlight," Carruth says. "So I would be surprised if a year from now there are still 10,000 tweets a month about the cronut."

Zandl says "it's going to wear off," but he says that's not necessarily a bad thing for Ansel.

Hopeful customers line up outside New York's Dominique Ansel Bakery to purchase cronuts. Photo: Richard Drew/AP

"It's put him on the map in a way that he could not have imagined," Zandl says. "I think he will be able to parlay it into something more for his business."

Ansel says he won't forsake his other pastries for the cronut.

"Before the cronut, we were very, very busy at the bakery," he says. "If the cronut is not here tomorrow, we'll still be very busy."

And despite the current frenzy, Ansel says, he is not interested in mass-producing the cronut or jacking up the price. For now, he is still charging the original $5 per cronut and limiting customers to two each.

The flavors change each month — July's is blackberry lime. Ansel says he hasn't yet decided on August's flavor, but is considering coconut and passion fruit.

Copyright 2013 NPR.

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