Rawon in Surabaya

Rawon is a beef soup from East Java and its colour is the point: an almost black broth, which comes from kluwek, the fermented seed of the kepayang tree. Fresh, that seed contains cyanogenic compounds and is genuinely toxic; it is made edible by boiling, then burying it in ash and earth for a month or more, during which fermentation breaks the compounds down and turns the kernel black and soft, at which point it is ground into the spice paste with shallot, garlic, candlenut, galangal, turmeric and lemongrass. The soup that results is dark, earthy and slightly sour, with cubes of beef, served over rice with bean sprouts, salted egg, fried shallots and sambal. Surabaya and the surrounding towns each argue for their own version.

What you actually see

• A black broth - the colour from fermented kluwek, not from soy or caramel.
• A detoxified seed - kepayang buried and fermented for weeks to make it edible.
• The standard accompaniments - bean sprouts, salted egg, fried shallots and sambal.
• Local rivalries - Surabaya, Nguling and other towns each claiming the best version.

When to go

All year; it is eaten at lunch as much as at dinner. A meal.

Honest expectations

The colour puts some people off before tasting. It is beef-based and not adaptable for vegetarians. Quality depends on the kluwek and varies widely between warung.

Nearby

Surabaya's old town, Ampel and the House of Sampoerna are in the city.