Dried beans are magical. What other protein and fiber source swells up to two or three times its original size when soaked in water. Think of what a hamburger would do if you soaked it overnight.
I did some pretty arcane calculations and found out that dried black beans and boneless skinless chicken breast each cost about 2 cents per gram of protein. Adults need about .8 grams of protein per every 1 kilogram of ideal body weight (1 kilo = 2.2 pounds). That’s about 55 grams of protein for a 150-pound person.
One 3.5 ounce chicken breast has about 45 grams of protein so if you eat that almost anything else is overkill. Not that chicken protein is a bad thing, but one cup of cooked beans gives you about 15 grams of protein and has the added benefit of providing about 15 grams of fiber.
Most people don’t get anywhere near the 20 to 25 grams of fiber needed per day and claim they would have to eat corrugated cardboard to reach the target. Not so. Soak some beans overnight, marvel at them in the morning, make this soup in the evening and get good low-fat protein and fiber.
Sort through the beans and look for stones masquerading as beans. Soak them overnight in about a quart of cold water. Smile when you see how they have grown in the morning. I let mine soak the rest of the day too.
Heat the oil in a large soup pot. Add the onion, garlic, bell pepper, fresh chilies, carrot, celery, and crushed red chilies. Sauté until the onion starts to become translucent.
Drain the beans saving the bean water. Add the beans, tomatoes, tomato paste, stock, sugar, herbs, vinegar, and bay leaf. Bring to a boil and simmer partially covered for 2 to 2 1/2 hours or until the beans are tender.
I added about a cup of bean water near the end as the soup had cooked down a bit and thickened. Some beans break down faster than others and thicken the soup while others hold their shape. You can create new synergies every time you make this if you vary the types of beans you use.
Discard the bay leaves. Season the soup to taste and sweep in the cilantro. Serve hot in warmed bowls.
This soup is very filling and makes a good main course to go with a salad.