“It’s something my mother used to do,” says chef David Zhou. He’s referring to his traditional crispy-duck dish. “Mum would get the duck and some prawn mince – it looks like fat but actually it’s diced prawn meat – and put a bit of batter on it. For her, it’s a good memory of home. [For] me too – it makes me feel like a little baby boy. ”

Despite being a personal favourite of the Chinese-born Zhou, Grandma Zhou's crispy minced prawn crusted duck, with sweet plum sauce and leafy greens isn’t on the menu at David’s, his much-loved yum cha restaurant in Prahran. One person is allowed to order the dish there: Grandma Zhou. For the rest of us, it’s only available to order through Deliveroo.

With David’s originally opening 16 years ago as an Oriental Teahouse on Chapel Street, the building Zhou first moved into was a former art studio. “There was nothing there,” he explains. “Very raw, very basic.” Zhou wheeled in boxes of teaware straight off the ship from China, and set about serving tea to whoever wandered in. “No logo, no name, no price,” he recalls. “I stuck it all in the middle of the room. But it was very warm and people started coming in who could smell the tea.”

As the teahouse got busier, Zhou introduced small dishes to keep his patrons drinking tea. To his annoyance, these dishes became more popular than the tea.

“I thought small yum-cha dishes would get people to pay attention to my tea,” he says. “But people rushed to the yum cha. They still don’t see my tea. But a lot of people started talking about it. Even back then people loved looking for this steamed prawn dumpling that was like it was in Shanghai at the time.”

So tight-knit was his regular clientele, when he moved around the corner to Cecil Street in 2012 and rechristened his business David’s, his customers followed en masse. Zhou says many of these regulars continued to ask for specific dishes not on the menu.

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“One of my ex-staff always goes back to the kitchen and asks the chefs for a noodle soup I used to cook just for me,” says Zhou. “So the staff thinks, ‘Well if he’s asking for it I have to do it.’ There are certain dishes like that. This restaurant has been a big learning curve, but I’ve also learnt a lot about people. The people who come here really get into their food, so I keep trying to push more new things.”

An example of these new things is David’s Country Comfort dish, aka sticky pork belly with chat potatoes. “I think if my grandpa looked at it, he’d think it very authentic,” says Zhou of the pairing. “But in China you don’t see that dish, because [China] uses mainly egg, not potato. The egg over there is a local food; here, the potato represents another local staple. I think inventing is important. We’re always reinventing ourselves but we always keep our core.”

This balance of tradition and innovation has seen Zhou embrace the rise of online ordering and delivery services like Deliveroo. It makes sense – Zhou’s regulars have long been tailoring their interactions with David’s. It’s part of his success. “It’s really customer focused,” says Zhou of the delivery service. “I respect these people. And I know it’s hard work. Just like this restaurant.”

Grandma Zhou's crispy minced prawn crusted duck, with sweet plum sauce and leafy greens is no longer available.

This article is presented in partnership with Deliveroo.