For those unfamiliar with this dish, "Sinigang," can be simply described as stew, but not just an ordinary stew. It is a sour stew using some fresh vegetables or fruits as souring agents. As in my case here in my neck of the woods, I use the powdered form for souring agent as the fresh ones aren't available. Back in the Philippines my mother had used different kinds such as santol, kamias, unriped mangoes, salomague or sampalok....OMG, just thinking of these fruits makes me salivate. These fruits are so sour and make really good Sour Soup.
Sinigang is one of the easiest dish to prepare and very forgiving. There is no right or wrong way as long as its broth is sour. For the veggies, you can use any vegetable you may have like eggplants, green beans, kangkong, etc. Sinigang can be fish, shrimps or pork.