I hadn’t really planned on posting this recipe but a friend who went on a trip to Indonesia with me asked for this. The reason is because I’m a bit of a purist when it comes to blogging and I prefer to avoid using pastes or instant mixes as nothing beats the flavour of fresh ingredients, but I felt I would bend the rules this time because this recipe turned up almost like the real thing (or so I think!).
I used to be really frightened of travelling to Indonesia because of two previous bad experiences of food poisoning when I travelled to Bintan and Bali in the past, and I did go through the phase of not daring to eat local food. But in recent years when I’ve had to travel more frequently to Indonesia, I’ve discovered how crazy amazing the dishes are. On a recent trip to Bandung, our hosts discovered how much I love Sup Rawon and they made it a point not just to feed us the best Rawon in the city, they gave us packets of Rawon paste so that we could continue to enjoy the same flavours back home.
Sup Rawon is pretty unusual as it is not just any beef soup. The distinctive of the soup is that it is jet black in colour from the buah keluak. What is buah keluak? There doesn’t seem to be a proper English name for this but the scientific name is pangium edule – this is a fruit that grows in Indonesia and is actually poisonous because of its hydrogen cyanide content. The fruit has to be prepared by boiling and then buried in ash and earth for more than a month in a fermentation process that turns the white nut flesh to a dark brown or black colour. It is this fruit that gives Rawon its distinctive black colour as well as a truly umami and rich and slightly bitter taste.
The use of buah keluak is not just in Indonesian dishes but also in peranakan (fusion Malay-Chinese culture in the Straits of Malaya) food. One of my favorite dishes is Ayam Buah Keluak which is a kind of chicken curry with buah keluak. In this dish the nut flesh is removed and mixed with spices, sugar and sometimes even meat and the filling put back into the shell and cooked in the curry. As a peranakan specialty dish it is not cheap and the quality of a peranakan food restaurant is pretty much judged on the preparation of the buah keluak.
Anyway the use of buah keluak in Sup Rawon is simpler as the nut is simply cooked into the soup. There are few more flavourful soups that I have ever eaten, which makes the long preparation for this soup well worth it.
Instant Pot Sup Rawon (Indonesian Beef Soup)
- 1 kg beef cubes (best beef cuts are either beef shin or beef brisket)
- 1 packet of beef Rawon seasoning mix (available in Singapore in Mustafa; if not there are also good Rawon paste recipes out there)
- 6 buah keluak* (pangium edule seeds)
- 1 one-inch knob of galangal, peeled and sliced
- 2 lemon grass stems
- 5-6 kaffir lime leaves
- 2-3 tbsp chopped spring onions
- 1 tsp sugar substitute
- About 3-4 L water
- 2-3 tbsp peanut oil
- 2-3 salted ducks eggs, boiled and sliced in half (optional)
- 200g bean sprouts, briefly blanched
- A bunch of coriander leaves (optional, for garnishing)
- Soak the buah keluak for 5-6 days in water, changing the water daily. When ready, use a meat mallet to tap a hole at hilum (attachment scar) of the nut. Use a small teaspoon to scoop out the contents of the nut and run the buah keluak contents in a food processor to break up the nut flesh. Set aside.
- Remove the outer leaves of the lemon grass stalks and using the heel of the chopper, bruise the lemongrass stems.
- Turn the Instant Pot on and put on sauté mode. Heat up the peanut oil, then sear the beef cubes in batches till browned on all sides. Set aside.
- In the same pot, sauté the Instant Rawon paste, galangal slices, lemongrass stalks and buah keluak flesh for 2-3 minutes, then add the beef back into the pot. Add the water (up to the 4L mark), kaffir lime leaves and sugar substitute and mix well, ensuring that the beef pieces are fully immersed.
- Turn off the sauté mode and close the pot, putting the valve into the sealed position.
- Put the pot on manual high pressure for 50 minutes.
- When done, allow natural pressure release. Skim off any oil on the surface of the soup.
- Ladle the soup into bowls and sprinkle 1 tsp of spring onions into each bowl. Garnish with a sprig of coriander.
- Serve the soup hot with blanched bean sprouts, cauliflower rice and half a salted duck egg.
* the use of buah keluak is almost mandatory even when using a paste as this increased the intensity of the soup flavour. The tricky thing in Singapore is getting fresh buah keluak as it is usually sold in kilo bags and not all the nuts are good. So in my trip to Bandung I was really happy to have had a chance to visit a large supermarket to pick up several small bags of good quality buah keluak.