This whole thing about having a little bowl of Thai soup with a couple of mini spring rolls on the side served to you as the initial part of a lunch special is done only at Thai restaurants outside Thailand. When it comes to modern Thai cuisine, a soup is not served as a separate course to be consumed as a stand-alone item; it is considered as much an entrée as, say, a curry or a stir-fry. That is to say, it's kap khao (กับข้าว), something to eat with the main component of a typical Thai meal ensemble: rice.
Once in a while, I hear comments about how plain, brothy Thai soups in the kaeng chuet (แกงจืด) family (to which this soup belongs) are "too salty." The reason is simply that they're intentionally seasoned in anticipation of the bland rice with which they're to be consumed.
This soup, for example, looks anemic. But what isn't obvious from looking at it is the powerful ingredients that go into the dish, making it something that, even though doesn't invite attention, demands respect. I could pour a big ladle of this soup over a bowl of rice and call it a meal. Quick, fuss-free, satisfying.
But if I have friends over, I may incorporate this soup into a more elaborate meal. One consisting of a plate of fried fish with Thai three-flavored sauce, a plate of raw and steamed vegetables with a relish, and a bowl of this light soup comes to mind.
What powerful ingredients go into this soup?
You've seen the dynamic trio of garlic, white peppercorns, and cilantro roots (or stems) before. Remember the marinades for turmeric grilled chicken and honey baked chicken? The same paste is also used here to season the pork resulting in not only flavorful pork balls that make up for the blandness of the tofu but also a delicious and fragrant broth that starts out as plain water.