I made this dish for lunch a few months ago, before it got too warm and humid for hot soups. I roasted sweet potatoes, carrots, onions, and scallions (but mostly sweet potatoes), then pureed them and thinned with water until I got a nicely rich, rustic soup.
For the other components, I started by simmering some canned black beans in a bit of water to soften them (I like to cook canned beans - I feel it softens them a bit and exorcises most off flavors), then drained them and added the beans to the soup and used their cooking water to cook some jasmine rice, which turned the rice a light purple that contrasted nicely with the orange of the soup and the green of the roasted scallions I saved to use as a garnish. Cooking the beans in a small amount of water maintained the intensity of color I needed for the rice, but I think I could have done a better job and ended up with darker rice.
Simple, satisfying, visually appealing. Not bad for an off-the-cuff lunch!