Bao's mother Phien makes a giant pot of bún bò Huế, a staple-dish in Vietnamese homes, that is eaten at least twice a month.
Bún translates as vermicelli noodles, bò is the beef, and Huế pays homage to the city in central Vietnam close to where Phien is from.
Huế also stipulates that this is a spicier version where chilli oil is used to flavour the broth.
"The fact that I still eat it now is the greatest testament to how good it is," he says.
But it wasn't always his favourite food. When he first tried it age five, the mere fact that one of the added ingredients was actually congealed pig's blood made him squirm. Over the years the homemade beef noodle soup gradually grew on him and by the time he turned eight he was able to eat it and enjoy it. Although, congealed pig's blood is also an ingredient that doesn't make it into the soup very often nowadays.
The star of the dish is actually Phien's secret spice concoctions and marinated beef sauce – most of the herbs she grows and picks fresh from her own garden.
"I actually don't know what the combination of these herbs and spices is," he says. Phien doesn't allow anyone to cook her recipes. "To serve this dish at Roll'd eateries, mum prepares the secret recipes and we make the noodle soup around these for our customers based on her strict instructions."
Growing up in Phien's kitchen, Bao was allowed to undertake small tasks like breaking off the roots of the bean sprouts. Everything else was Phien's territory, and when it comes to Vietnamese food, it still is.
"Bún bò Huế is about eating with a big noisy family."
"I make bún bò Huế for myself when mum's away on holidays, she will never try it," he says. "Mum will only eat my food when I cook western dishes for her, but never my Vietnamese dishes."
Phien's love for cooking began when she migrated to Australia. Before that, when she was a schoolteacher in Vietnam, she never really had the time. But, in 1981 when Phien, her husband and two of her four children (Bao and his younger sister Quinnie were born in Australia) escaped the war in Vietnam by boat and settled in Melbourne, the duties of cooking for her family and extended relatives, most of whom lived under the same roof, became her responsibility.
Here, Phien spent most of her time in the kitchen with her sister, which is where she first learned how to make this unique beef noodle soup and is how the recipe got handed down to her.
"At age 25 mum found herself cooking for 30 people at a time, and that's how she built her skill set," he says. "Together with her sister they refined the recipe and based on new ingredients mum sourced locally in Melbourne, she put her own spin on it and is now the dish I ask her to cook for me every year for my birthday – as long as I give her four hours' notice, which is how long it takes for her to shop, prep and cook whatever meal from her repertoire."
The Bún bò Huế broth is rich and has a full-bodied strong flavour. Mostly it's the lemongrass that gives the broth that more tangy taste.
"While you can add different cuts of beef protein to the soup what makes mum's recipe stand-out from other versions is that she marinates the meat prior to adding it into the broth," he says. "She also uses a more tender cut, a brisket, rather than the boiled pork knuckle and other meats more common in the traditional version."
At Roll'd they also add bean shoots, spring onion, coriander and mint, which gives the dish that extra hit of freshness, flavour and texture and as a bonus it's healthy.
The dish also features heavily during Tet, the Vietnamese Lunar New Year, which is the most important celebration in Vietnamese culture and lasts for two weeks.
"You know mum has cooked Bún bò Huế, for at least 40 people, as soon as you enter the home," he says. "The aroma of the beef being marinated and the intensity of the home-grown lemongrass are so acute that the smell probably hangs around for 2–3 days."
The soup is served on many occasions with a side of spring rolls or vegetables.
Everything Bao knows about Vietnamese cuisine he learned by watching and cooking with Phien.
"From mum's skills I honed that no matter who you cook for or for how many people, you can make things pretty quickly and simply and they will still taste great," he says. The secret to this lies in preparing sauces ahead of time, this way you can do things when they need to be done at a quick pace and the result is delicious.
A few other of Phien's unique flavours served at Roll'd include Vietnamese Pho with various meat, seafood and vegetarian options and Bun noodle salad, another Vietnamese staple dish but with a twist thanks to Phien's home-made fish sauce dressing.
"For me, bún bò Huế is about eating with a big noisy family while sitting on the floor in our home in Oakleigh, Victoria. Those are the memories of my childhood," he says.
And as for Phien's cooking secrets, "she has written down her recipes in a little black book that I have claimed to own in the future."
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