Kumara Soup

Directions

1. 1
   Melt the butter in a thick bottomed saucepan, add the onion and celery and cook gently for about 5 minutes until transparent.
2. 2
   Stir in the flour, mixing it in carefully to ensure that no lumps of flour are left; continue cooking gently for another 5 minutes, taking care that the vegetables don't brown.
3. 3
   Remove from heat and add the kumara, then slowly add the stock' stirring to mix all ingredients.
4. 4
   Return pan to the heat and bring soup to the boil, add the bouquet garni then simmer for 45-50 minutes, stirring occasionally.
5. 5
   Take the pan off the heat, remove the bouquet garni and any foam that has formed.
6. 6
   Allow to cool slightly then liquidize soup in a blender.
7. 7
   Add seasoning to taste then re-heat if necessary before serving.