You can make this soup with just about any two beans, although I usually make it with black beans as one of the two, and sometimes as both.  Pictured is black bean and kidney bean (the Stendahl); another favorite is black bean and cannelini (the Newspaper).  I suppose there’s nothing stopping you from making it with three beans.  It works quite well in vegetarian form, though Sarah likes it best when it’s made with chorizo and chicken stock.

Two Bean Soup

1/4 cup olive oil
Small onion, chopped fine
1 clove garlic, minced
1/4 cup chorizo, diced (optional)
1 T finely chopped poblano pepper (you can also use jalapeno, but may want to use less)
Two 15.5 ounce cans of beans, rinsed
One 32 ounce carton of vegetable broth or chicken broth
Plain yogurt
Small bunch of cilantro, chopped

Over a medium heat, cook the onions and garlic in olive oil until soft.  Add chorizo, if you’re using it, and the pepper, and cook for a minute or so.  Add beans and stock.  Increase heat and bring to a boil.  Lower heat and simmer for about an hour.  If you like a smoother soup, you can puree it with an immersion blender.  Serve with a dollop of yogurt and a sprinkle of cilantro.  This soup tastes better the next day, and even better the day after that.