Stones for dinner? Not quite.
These rock-like objects are the hard-shelled seeds of the kepayang tree (Pangium edule), which grows wild in Indonesia and Malaysia. Known as kluwak in Indonesian and buah keluak in Malaysian, they are an essential ingredient in rawon, an east Javanese beef or chicken stew, and in ayam/babi buah keluak, a Malaysian Nonya chicken or pork specialty.
I'd been eyeing the piles of kluwak at Indonesian vendors' stalls in Kuala Lumpur's Chow Kit market for some time. It was the wonderfully rich rawon served by a Javanese vendor at nearby Restoran TAR that set me on the path to purchase.
Studded with tiny, barely sprouted soy beans, this beefy bowl begged to be eaten on a cold night in front of a roaring fire. No chance of that in KL, though I might set the aircon to high before I sit down to my own version.
The pale 'meat' of raw kluwak are poisonous. On Java, where most commercially-sold kluwak originate, they are soaked and boiled to neutralize their hydrocyanic acid. The pitch-black meat of the processed seeds is soft and oily, like half-cooled tar (some might say opium), and smells woodsy, like a forest floor after a long rain. It tastes a bit like a strong mushroom, with the barest repellant-yet-alluring hint of truffle.
Before being blended into rawon the kluwak is ground to a paste. The depth of flavor it lends to this humble dish is difficult to describe, but I've rarely been as taken by a bowl of beef soup. A better cook than I would no doubt figure a way to incorporate this intriguingly fungi-esque ingredient into a western dish or two.
Kluwak are easily available (already shelled) in the US - on Amazon, no less. Fans of (very) slow-cooked, big flavors might want to try this recipe, posted by an Indonesian food blogger, for rawon made with oxtail, or this one, for Nonya ayam buah keluak (chicken cooked with kluwak).