KBL (Kadyos, Baboy, at Langka) Recipe
The sourness of this "sinigang" is from batuan.
"Sinigang" doesn't always mean the dish made with sampaloc or tamarind. In fact, the root word is "sigang" or to cook or stew in a broth. Many dishes have been made into a sinigang but not all are made with sampaloc.
Take this KBL recipe. It's a "sinigang" that's very similar to the sinigang sa sampaloc but its sourness comes from the regional native fruit batuan or batwan. If you're Ilonggo, you know this to be a green fruit that grows on trees. It's abundant in Negros in the Visayas. It's naturally green, but turns yellow as it matures. It's best used, however, while still green and either a little bruised or has browned spots which are normal for these fruits when sold.
To use the batuan in this recipe, wash and then slice the fruits. You can leave the large seed when added to the pot.
As for the other ingredient that's unique to this dish, the kadyos in the KBL is a black pigeon pea. Just like the batuan, kadyos is a regional ingredient that those in Visayas are familiar with since these are abundant in the south. As with other dried beans, kadyos should be soaked in water overnight before adding and cooking in the recipe.
This regional recipe brings the batuan and kadyos together with pork and jackfruit or langka into this sour-tasting soup. If you love the different kinds of sinigang, then you have to try this version, too.