| 1 | *note: finely chopped parsley may be substituted for coriander leaves. |
| 2 | Wash lentils in several changes of cold water, or place in a sieve and run water through them. |
| 3 | Drain. |
| 4 | Put lentils in a large pot with 8 cups water, spring onion, garlic if used, oil and coriander or parsley (or a combination of the two if preferred). |
| 5 | Bring to the boil, cover pan and simmer on low heat for 1 hour or until lentils are soft. |
| 6 | Put water and flour in a screw top jar, seal and shake until thoroughly combined. |
| 7 | This prevents lumps forming. |
| 8 | Pour this gradually into boiling soup, stirring constantly, until thickened slightly. |
| 9 | Add vinegar and salt and pepper to taste. |
| 10 | Return to the boil, boil gently for 5 minutes, then serve hot |