The retired driver remembers stopping by a roadside stall to buy kacang putih for his young charge in the 1960s.
The boy who loved the snack was Prime Minister Lee Hsien Loong, now 63. He would often ask for kacang putih after classes ended at Nanyang Primary in the afternoon.
PM Lee posted a picture of the encounter on his Facebook page on Sunday, and it has drawn more than 50,000 likes.
Mr Woo, a volunteer at a temple near Redhill Food Centre, heard that PM Lee was having dinner at the food centre, so he went there to get a glimpse of him.
The retiree had tried to meet PM Lee when he visited the food centre on two previous occasions but he could not get past the large crowds.
Mr Woo said in Mandarin: "I approached him and asked him if he recognised me.
"He looked a bit lost at first but when I told him that I used to be their driver, he said 'Koon Seng' right away.
PICTURE WITH PM
"PM Lee then took out his phone and asked his bodyguard to take a picture of us together. He even asked for my home address so that he could send the picture to me."
Mr Woo, who lives with his wife in a three-room flat at Stirling Road, had fond memories of his years working for the Lees.
He was a PAP member and was recommended to the job by a friend, who worked as a bodyguard.
"I was paid $150 a month, which was a large sum of money at that time," said Mr Woo, who cycled to the Lees' residence at Oxley Road every morning.
He would drive - in a Morris Minor - PM Lee and his two siblings to their school at Stevens Road. Later in the morning, he would take then Prime Minister Lee Kuan Yew's father, Mr Lee Chin Koon, to work.
Mr Woo would then take PM Lee's mother, Madam Kwa Geok Choo, to her law firm at Market Street. Former Prime Minister Lee was chauffeured by another driver.
With a smile, Mr Woo said of PM Lee and his siblings when they were children: "They were very well-behaved and polite.
"Their father was strict with them, and would not hesitate to scold them if they misbehaved. How else would they all have turned out so well?"
As former PM Lee grew in prominence, the protection of his family became an issue and a bodyguard took over as driver.
Mr Woo then obtained a canteen licence at Tanglin Technical School, now Tanglin Secondary, and operated a drink stall for 36 years.
Mr Woo, who has two sons in their 40s and a 22-year-old granddaughter, said that he was surprised by the attention PM Lee's Facebook post received. He had found out about PM Lee's post from a friend and was interviewed by Chinese daily Lianhe Wanbao.
"When I went to the polyclinic on Tuesday afternoon, the pharmacist recognised me and asked if I was the man who used to be PM Lee's driver."
His wife, Madam Lai Yu Moi, 80, said: "We were dating when he was working as a driver, and I never asked him much about it, thinking it was just a regular job."
This article was first published on March 5, 2015.
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