Momh Meah‘s first trip to Thailand was a search for money to support her brothers and sisters. She was 12 years old. For the next decade, she climbed trees and picked fruit, all day, every day. It was back-breaking work. When an injury forced her to return home to Battambang, she was severely depressed.

Less than three years later, Meah’s second trip to Thailand couldn’t have been more different. At 25 years old, she was a chef with two years’ experience. In Bangkok, she ate in the restaurant that has this week been named Asia’s best. She swapped cooking tips with one of Australia’s most famous chefs and posted Instagram pictures wearing oversized sunglasses. Her life was unrecognisable.

She was the head chef at Jaan Bai.

As soon as you approach the floor-to-ceiling glass windows of Jaan Bai, Battambang’s new training restaurant set up by the Cambodian Children’s Trust (CCT), you can tell it’s a slick operation. The artificial turf, tiny wooden tables and surrealist paintings outside look more like an art installation than a dining area. The menu, featuring a mixture of Thai and Khmer cuisines, has a homemade feel with witticisms about having “fancy water filters” and none of “that MSG stuff”.

Over a latte on a recent morning, Tom O’Sullivan, a tattooed, shaggy-haired Melbournite and one of two Australians working in supervisor roles at Jaan Bai, explained why he was tired.

“We’ve been busy beyond what we expected – really quite tested for a young restaurant,” he said.

It’s no wonder. There aren’t many places like Jaan Bai in Battambang, a sleepy riverside town known for a particularly horrible Khmer Rouge history and a large rice output. Increasingly, however, its reputation is changing. As the home of non-profit Phare Ponleu Selpak, whose visual arts program has produced some of the country’s most promising painters, and a number of small galleries, the city is now known as an arts destination. For a small place, Battambang has a lot of charm.

It was that charm which drew the attention of Tara Winkler, the 28-year-old founder of CCT, which helps vulnerable children escape poverty. As a traveller in 2005, she wanted to see the “real” Cambodia. She ended up staying more than six years.

To this day, Winkler loves the city for its relaxed pace and rich cultural history, she wrote in an email.

“As it was a Khmer Rouge stronghold, the city and its people endured so much horror and suffering, which left a legacy of hardship and poverty.

“I think there’s so much potential for this city and its youth and I’m honoured to be able to contribute to helping them realise that potential.”

Today, CCT works with more than 300 children and their families. The organisation runs several education programmes and two social enterprises: Sammaki Gallery and now Jaan Bai, or “rice bowl” in Khmer, which opened its doors in October.

The décor is stylish but friendly – colourful paintings by local artists hang on the walls – and the same goes for the menu. Juicy pulled pork sliders are stuffed with beetroot and red cabbage and served with salty handcut chips. Lemongrass basil chicken is spicy and fresh, making use of herbs picked in the restaurant garden. Most dishes cost around $3.

Jaan Bai wasn’t initially intended to be a restaurant. The idea began as a barista training school for Cambodians, created with the sponsorship from Australia’s Vittoria coffee, one of the country’s largest manufacturers.

But Winkler “is not one to do something by halves”, O’Sullivan said.

A leading Australian restaurateur was also a long-term supporter of CCT: John Fink, of Sydney’s Quay and Otto. He came on board and brought with him David Thompson, whose Michelin-starred Bangkok eatery, Namh, was this week named Asia’s best in S.Pellegrino’s awards for 2014.

Both Fink and Thompson have provided onsite training to some 20 local staff that come through CCT, and agreed to host trainees in their restaurants. They also attended the opening in Battambang last year.

“We have all learned so much from them, especially Meah who was lucky enough to spend some time training in David’s restaurant, Nahm,” said Winkler.

It was Thompson who helped Momh perfect recipes that are now staples on the Jaan Bai menu, like the Kampot pepper crab with chili jam, her favourite dish.

Wearing a white chef’s apron, Momh explained that she learned a local way to cook the crab on the coast of Cambodia. The chili jam is Thompson’s.

“It’s kind of a perfect marriage of Thai and Khmer cuisine,” said O’Sullivan.

Unprompted, a middle-aged customer at a nearby table chimed in, “very good”, and Momh beamed.

The young chef likes talking about food. Her upper lip curls and she reveals a toothy grin. But when asked about her life before she came to work with CCT, it swiftly vanishes.

“Oh, it’s difficult, so much,” she said. “You want to know? I will tell you.”

It’s not a happy story. At eight months pregnant with Momh, her mother was abandoned by her husband. As a result, Momh said, her mother never loved her, and couldn’t support her children either in Cambodia or Thailand. When Momh was fired from her job after hurting her back, her mother scolded her horribly.

After returning to Battambang, she left for Phnom Penh, and took up sewing to support herself. It was a miserable time, she reflected, eyes welling up.

“When my mum came back from Thailand too, she found out she had HIV.”

Her mother severed all contact and, later, after bumping into Momh, pretended not to recognise her daughter.

“She said: ‘who’s that, coming to take the rice,’ ” Meah recalled in a tone that suggested she still didn’t quite believe it was true. There was no reconciliation.

Instead, Meah and her three siblings went to stay with her uncle. Eventually, she met a woman who wanted to help and encouraged Meah to stay with an orphanage but her uncle refused. Eventually he left too.

She agreed to go to the orphanage, and in 2010 met Winkler, who placed her in foster care and then CCTs’s hospitality training program. She went on to do two years at a Siem Reap hotel before coming to Jaan Bai.

“[Winkler] asked me: ‘Momh, what do you want to work as?’”

It was the first time Meah had been given that choice.

“I thought: ‘I can think about this question, too.’”