LULU GARCIA-NAVARRO, HOST:
There's food that's old. Then there's food that's gone bad. And then there's beef soup that's been simmering for 45 years. At one Bangkok eatery, customers can't get enough. Michael Sullivan reports.
MICHAEL SULLIVAN, BYLINE: Nattapong Kaweenantawong has seen some of the press his soup has gotten recently. And he wants to set the record straight on what he thinks is a popular misconception.
NATTAPONG KAWEENANTAWONG: (Through interpreter) Lots of people think we never clean the pot. But we clean it every evening. We remove the soup from the pot then keep a little bit simmering overnight.
SULLIVAN: And that little bit forms the stock of the next day's soup. So, yes, at least a taste of what you put in your mouth is 45 years old. The pot at Wattana Panich sits near the sidewalk on a busy street in the city's Ekkamai neighborhood. And it's enormous - about five feet in diameter and 2 1/2 feet deep, brimming with chunks of beef bumping into one another as he stirs the sweet, dark brew.
KAWEENANTAWONG: (Through interpreter) Since my grandfather's time, we've never really had a recipe. So the person making the soup will constantly have to taste it to know what needs to be added.
SULLIVAN: He says some of the ingredients include nearly a dozen Chinese herbs, plus garlic, cinnamon, black pepper and cilantro root. And then there's the beef. He goes through about 150 pounds a day.
KAWEENANTAWONG: (Through interpreter) We put the whole thing into the pot, so it absorbs all the flavors. Then after three hours, we take it out and cut it into smaller pieces then cook it for another four hours.
SULLIVAN: The result is an aromatic blend of spices, herbs and beef that's been drawing repeat business since his grandfather started making the soup in another location more than 60 years ago.
INDI RAKAMNUAYKIT: I am Indi Rakamnuaykit.
SULLIVAN: And how long have you been coming here?
RAKAMNUAYKIT: For basically as long as I can remember. I mean, my earliest memory, again, was when I was 5, 6 maybe.
SULLIVAN: He's 24 now and says his father has been coming here since he was 11. Indi says he loves the taste of the marrow and the fat and, of course, the beef.
RAKAMNUAYKIT: The quality has never changed. It's always been this good. I feel like some other places, you're not really sure what goes into it - maybe, you know, some MSG. You don't really know. But here, you really taste the beef.
SULLIVAN: Ussani Susot is a first time customer. She's Thai and runs a company that does day tours around Bangkok. She gives the soup a 10 and doesn't fret much about the idea of slurping soup that's been simmering for 45 years.
USSANI SUSOT: For Asian people, we're quite familiar with fermented thing and something that you age for really long. So this not bother me at all.
SULLIVAN: And do you think that process actually helps the taste of the soup?
SUSOT: I believe so. If you stew it for so long, you can bring out all the flavor from the bone that they put inside, all the herb, the condiment, everything they put inside it.
SULLIVAN: And it's not just Thais who come.
CHRIS BRADY: My name is Chris. I'm from Melbourne. I'm here for business.
SULLIVAN: Chris Brady says he first came about seven years ago, lured by a friend from Singapore. He comes to Bangkok three to four times a year. And every trip, he says, has to include a visit to Wattana Panich.
BRADY: I think they have the best beef noodle soup in the world - without question.
BRADY: It's the stock. You know, there's a bit of sweetness. There's a bit of - I mean, there's a real beefiness to it. There's a lot of depth to the flavor. It's not just, you know, a bit of Maggi beef stock mixed in with some hot water.
SULLIVAN: Owner Nattapong says his 12-year-old daughter has expressed interest in taking charge when she's old enough and he, tired enough. And he really hopes she doesn't change her mind. Maybe that soup can simmer for a century. For NPR News, I'm Michael Sullivan in Bangkok. Transcript provided by NPR, Copyright NPR.