“Thank you for your warmth and kindness, sending my father (and me) your special sambal belacan all these years!,” Lee tweeted.

“I hope you enjoy making it as much as we enjoy eating it!,” said Lee, ending his post with a smiley emoticon.

Lee’s posting came in response to a tweet by Tunku Azizah on Oct 25 when she shared the secret of how her home-made sambal belacan was a hit with Lee’s father, Singapore’s founding prime minister Lee Kuan Yew.

Tunku Azizah, as cheminahsayang on Twitter, disclosed that she was, at one time, the “official supplier” of sambal belacan to Kuan Yew. She still supplies sambal belacan to the republic, she said, and the sauce is now enjoyed by Kuan Yew’s son and current Prime Minister Lee Hsien Loong.

“I had long wanted to share this (secret) with Malaysians. I was once the official sambal belacan supplier to the Prime Minister of Singapore … Datuk Lee Kuan Yew … and now supply to his son, PM Lee,” she posted.

Tunku Azizah had also shared a photograph of a letter written by Kuan Yew.

The letter, dated July 23, 2009, read: “The six packets of (sambal) belacan you gave me were delicious. I shared them with my two sons. They have all been consumed. It is the best chilli belacan we have tasted. Can my family have a few more?

“Sorry to trouble you over this. It makes so many dishes taste better.”

Tunku Azizah, who had posted the picture on May 2 last year, said the letter was most meaningful to her “… all because of sambal belacan … I was deeply touched,” Her Majesty said.

Her Instagram account holds a collection of her recipes, reflecting her popularity as a member of the royalty who loves cooking.