Cannellini and Black Bean Soup with Mustard Greens

This soup is a nice twist on a kale and black bean soup. I had about a cup or so of dried black beans, a cup and a half of dried cannellini beans, and a bunch of mustard greens from the farmer's market. Here's the result:

I soaked the beans overnight.

I took a head of garlic, peeled, and sliced, and sauteed that in some oil in the bottom of my soup pot along with some spices: about two teaspoons of each of turmeric and paprika, and a tablespoon of chili powder (but the chili powder I currently have is really weak). Aside from flavor and nutrition, the spices give a nice color to the soup, which would otherwise be kind of grey. Add water (about a quart and a half), and beans. Bring to a soft boil for 45 minutes to an hour, until the beans give but aren't quite cooked yet. Then add mustard greens that have been chopped into big bite-sized pieces, and turn down the heat to a big simmer for 15 minutes, or as desired. Add salt to taste.