In a large casserole dish, heat the oil and fry the onions, celery, carrots and garlic until soft. Add chili powder, cumin, salt, pepper, cook for 1 min..Add bouillon, half the black beans and corn. Bring to a boil. in the mean time, put the rest of the beans, tomatoes and lime juice in the blender. Add this to the casserole dish and let simmer for 15 min.