(CNN) — Hidden above a terminal car park and tucked away at the end of a dingy corridor lies Singapore airport's best-kept secret.
Its staff canteens.
World's apart from the glitzy hub's rooftop swimming pool and butterfly garden, these loud hawker markets serve up some of the best -- and cheapest -- food not just in the airport, but in Singapore.
Their name, however, is a ruse: the staff canteens at Changi airport are, in fact, open to the public and their authentic, no-frills fare has made them an underground hit.
Chow down with the staff
Finding the staff canteens is -- intentionally -- difficult.
Built to provide workers at the award-winning airport with an affordable place to eat, the hawker markets are off the beaten track and not listed on the airport's food directories.
Those with a sharp eye, however, will spot "staff canteen" signs dotted around terminals 1 and 2.
To find the canteen, take the lift to the basement ...
"The eateries are located at the public areas of the airport as not all staff have access to the restricted areas," says Ivan Tan, senior vice president of communications at Changi airport.
He adds that the canteens have always technically been available to the public since being built in 1981 (Terminal 1) and 1991 (Terminal 2): the airport just didn't realize people would want to eat at them.
Moritz Rossmanith, who lives in Singapore and runs the The Jet Sets travel blog, says, "I heard about the canteen at T2 through word-of-mouth.
"It's a trip down memory lane to what food courts in Singapore used to be like in terms of pricing and retro design. A lot of them are very glamorous now.
"Airports don't usually reflect what a country's food is about ... but the staff canteens have an authentic array of local food."
The two canteens have become so popular, Tan adds, that local families and foodies travel to the airport specifically to eat at them.
What's on the menu?
The airport carefully controls the mix of canteen stalls, Tan explains, to ensure all nationalities employed at the hub are catered for -- and it insists that the staff get a good price.
A sign for the "staff canteen".
Halal, vegetarian, Korean, Vietnamese, Indian, Malay, Cantonese, Taiwanese, Western, and -- of course -- Singaporean cuisines are all on offer.
The atmosphere inside both canteens is decidedly unlike most of Singapore's gleaming airport: food is dished up on paper plates, eaten with brightly colored plastic cutlery and there is no air conditioning.
Like the food itself the clientele is eclectic, ranging from cops, security staff and cleaners to air hostesses, pilots and smart travelers with designer shopping bags.
Tan says the most popular dishes are the roti prata (Indian fried pancake), Taiwanese hot pot mackerel, nasi padang (Malay mixed rice) and fried Hokkien prawn mee.
For the public, the meals range in price from $2 to $5.
Finding the staff canteens
So how do you find the staff canteens? Following the signs isn't quite enough.
Terminal 1 has the biggest canteen, with more than 25 stalls and its opening hours are in line with that of the staff: 7 a.m. until 8 p.m.
Follow the signs for the restrooms (you're looking for the ones with the red doors), then take the nearest lift down to basement 1. When you arrive turn right, and the canteen will be in front of you.
For the Terminal 2 canteen, locate Starbucks on level two and take the nearest lift to the car park at level 3: from here walk up the staircase, turn left and look for the unlabeled iron door.
Behind this could well be the best (and cheapest) airport meal you'll ever eat.