Boil black beans in water for 2 minutes; remove from heat. Let soak in cooking water for 1 hour, or overnight if preferred. Saute celery, onion, and bell pepper in oil, until slightly tender. Then in bean soup, add salt, cilantro, and saute vegetables. Covered and simmer, until beans are soft, about 2 to 3 hours. Slightly mash some beans, and stir. In frying pan, warm up tortillas on both sides until they are bendable. Put a tortilla in bowl, then ladle black bean soup on top of the tortilla. Makes 2 servings.