When the British ruled India, they wanted soup with their meals. Indian cuisine doesn't really feature soup, so the cooks came up with this. The name comes from two Tamil words meaning 'pepper water'. While recipes for this vary a great deal, the basic idea is it's a smooth curry-flavoured vegetable-based soup with maybe a bit of chicken and rice or lentils to give it body. It's not often seen these days, but maybe it's time for a revival.
Fresh coriander/cilantro to garnish.