Life In Food With Violet Oon: Buah keluak, the black diamond of Peranakan cooking

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SINGAPORE - The buah keluak nut, which I call the black diamond of Peranakan cooking, evokes in me feelings of awe and admiration.

Its correct preparation and cooking were the gold standard of the culinary skills of a Peranakan maiden of the old school. If she did not crack the shell right and broke it instead of crafting a smooth, round opening just large enough to insert a teaspoon, she was considered unfit for marriage. This and pounding the flesh right were the litmus tests of her cooking skills.

By the time I turned up on the scene in 1949, World War II had changed that world and women like my mother were blazing other trails of success.

My mother Nancy Oon neither cooked nor sewed. A Raffles Girls' School alumna, she possessed shorthand skills of 180 words a minute. This landed her a brief stint as secretary to Mr David Marshall when he was Chief Minister of Singapore in the 1950s.

Not having had the advantage of piano or other lessons of an artistic nature, she enthusiastically enrolled me for every type of course possible - piano, ballet, singing, Balinese dancing, jazz - everything but cooking.

Although I was brought up on the threshold of the women's liberation movement, I decided to play contrarian by behaving like a classic Nonya girl, entertaining the men of the household - namely my father Oon Beng Soon - with food and singing at the piano after dinner.

My decision came about after we lived for a few months with my grand-uncle Khoo Heng Loon and his wife Nanny Zecha, so famed for her culinary skills that the Cold Storage supermarket at the end of Emerald Hill Road ordered two freshly baked kueh lapis from her every day.

Hooked, I asked Auntie Nanny to teach me how to make kueh and Indonesian dishes such as daging chabek and ayam goreng.

From my father's sisters, mainly my aunt Nona Bong, I learnt the whole repertoire of Singapore Nonya cooking, all while I was 16 to 18.

Growing up during the women's liberation movement, it was considered out of date and demeaning for women of education who had "burned the bra" to cook. The wok and ladle were thrown out of a thinking woman's arsenal as they were considered symbols of bondage to the patriarchy.

This explains why, in my generation, my focus on cooking and the feminine arts made me unusual.

In October 1980, I was inducted in France as a Noble Dame of the Grand Order of Rocamadour du Diamant Noir - the Black Diamond of Perigord, an elusive black truffle that is buried under the earth and has to be sniffed out by pigs or dogs.

The reverence in which the French hold nature's gifts of the harvest taught me to treasure our own buah keluak.

Peranakans know that the buah keluak tree and its nuts are poisonous and the nuts need to be buried in ash for 40 days to remove the toxins. When the nuts are unearthed, the whole shell and flesh will have turned black.

The nut is also a key ingredient in Malay cuisine, especially in the dish of rawon, an Indonesian beef soup.

I find the buah keluak shares a similar taste profile of earthy smokiness with the truffles of Perigord, and Piedmont in Italy. Thus, at the opening of the Baba Bling exhibition in the Musee du Quai Branly in Paris in 2010, I billed the buah keluak as our very own Singapore black diamond.

At the private pre-opening show, I demonstrated how to cook and serve buah keluak ayam to the guests.

Buah keluak ayam is a staple of the Lunar New Year table of the Peranakans. I share here this classic as well as a dish that has become popular in recent years - buah keluak fried rice - with the addition of Piedmont black truffles.

The fresh truffle season ends in March and the truffles here are provided by supplier Classic Fine Foods.

Today, not just women, but also men, are enticed by the lure of the kitchen. The pandemic-induced lifestyle of social distancing and staying home has inspired a new wave of culinary crusaders, all intent on learning and getting it right.

They are more than ready to take on the intricacies of these dishes. I pass on the baton to them to cook and understand our black diamond, the buah keluak.


Buah Keluak Ayam

Spice paste (rempah)


6 candlenuts (buah keras)

200g shallots

10 fresh red chillies

20g galangal (lengkuas, also called blue ginger)

4cm turmeric root (kunyit)

20g belacan


1. Wash the candlenuts.

2. Peel the shallots and cut each into two to three pieces.

3. Slice red chillies into four pieces each.

4. Pound or grind the candlenuts, galangal, turmeric root, chillies and belacan, adding each ingredient in that order. Then add the shallots and pound to bind the ingredients into a semi-rough paste.

Buah Keluak Ayam


20 buah keluak, soaked in water for two to three days

50g minced pork

2 Tbs sugar

1 tsp salt

1 litre water

4 rounded Tbs tamarind paste

1 stalk serai (lemongrass)

½ cup vegetable oil

Spice paste (rempah)

1.5kg chicken, cut into 16 pieces


1. Crack open the smooth part of the buah keluak at the thicker end of the nut with a pestle on a mortar. Dig out the dark brown flesh with a teaspoon. Put aside the empty shell. Discard the flesh and shell if they smell rotten.

2. Clean the pestle and mortar and pound the buah keluak flesh till it is all mashed up. Push the flesh through a fine sieve.

3. Add the minced pork, 2 tsp of sugar and ¼ tsp of salt. Pound again till well mixed.

4. Fill the shells with the buah keluak mixture, smooth the top into a dome shape and keep aside.

5. Mix water with the tamarind and squeeze hard to extract juice. Discard seeds.

6. Smash the lemongrass.

7. Heat a wok over a high fire for about 30 seconds. Add ½ cup of oil. When the oil is hot, add the spice paste (rempah).

8. Stir-fry seven to eight minutes till the rempah darkens and oil exudes.

9. Add tamarind water, chicken, buah keluak and bruised serai, and the rest of the sugar and salt.

10. Bring to a boil over high heat, lower the heat and simmer for ½ hour or till the chicken is tender. Serves eight as part of a meal with rice.

How to eat

Scoop out the buah keluak flesh from the shell with a teaspoon. Mix with the gravy and spoon over steamed rice, add the chicken and enjoy.


Buah keluak fried rice

Titek spice paste (rempah titek)


5 dried chillies

100g shallots, peeled

4 candlenuts (buah keras)

10gm belacan


1. Soak dried chilies in hot water for 30 minutes to one hour to soften. Drain and squeeze dry. Cut each shallot into two to three pieces.

2. Pound or grind the ingredients into a semi-fine paste.

Buah keluah fried rice


50g dried prawns

6 Tbs oil

Titek spice paste (rempah titek)

200g prawns, shelled and sliced

600g cooked rice

80g buah keluak flesh, sieved

200g winged beans, sliced

½ tsp salt

2 tsp sugar

2 pink ginger flowers (bunga kantan)

1 black truffle


1. Soak dried prawns in water for two to four minutes. Drain.

2. Grind or pound till semi-fine.

3. Heat 4 Tbs of oil and fry the dried prawns till semi-crisp. Push aside.

4. Add 2 Tbs of oil and the titek spice paste (rempah titek). Stir-fry briefly before mixing in the dried prawns and fry for about five to six minutes till the oil exudes.

5. Add the sliced prawns and fry till semi-cooked and prawns turn red.

6. Add rice, sprinkle a little water over, cover with a lid and steam for a minute or two till steam rises. This will separate the rice grains.

7. Add buah keluak, sliced winged beans, salt and sugar, stir a few times and switch off the heat.

8. Remove from wok.

9. Plate and garnish with julienne of pink ginger flowers and petals round the side.

10. Shave a generous serving of black truffles over the top.

Where to buy buah keluak

Head to Tekka Market in Little India or Geylang Serai Market in Joo Chiat. Select heavy nuts as the lightweight ones may contain shrivelled flesh. If you stuff the buah keluak nuts to the brim, you will end up with extra empty shells.

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