Kangkung is ipomoea aquatica, a semiaquatic plant that grows in swamps. It is called kangkong in filipino, rau mung in vietnamese, phak bung in thai and kangkung in malaysian and indonesian. Both the hollow stalks and the leaves are edible although the stalks are tougher and take a bit longer to cook. Sambal is a generic term for chili-based sauces; there are a lot of varieties, we suggest using sambal oelek (available in the asian section of most groceries). If you use sambal belacan which is a chili and shrimp paste, you dont have to add shrimp paste separately, but youll probably have to make adjustments to the amounts. You can serve this as a vegetable dish alongside a meat dish. Its not totally vegetarian because shrimp paste is an ingredient; if you want to transform it into a vegetarian dish, just omit the shrimp paste.