Basic curry sauce

---------- Recipe via Meal-Master (tm) v8.04
  
       Title: Basic Curry Sauce
  Categories: Sauce
       Yield: 1 servings
  
       3 tb Vegetable oil or ghee
            -(clarified butter)
       1 lg Onion finely chopped
       4 cl Garlic peeled and sliced
   1 1/2    Inch piece root ginger
            -peeled and sliced
       2    Fleshy green chiles of
            -your choice de seeded and
            -veined then chopped
     1/2 ts Turmeric powder
     1/2 ts Ground cumin seed
     1/2 ts Ground coriander seed
       4 tb Plain passata (smooth,
            -thick, sieved tomatoes)
            -or
       1 tb Concentrated tomato purée
  
   This is the basis for many of the restaurant-style
   curries you'll find . The curry recipes use half or
   two-thirds of the amount that this recipe gives. If
   you have some left over you could use it in a
   vegetable curry or freeze it. The recipe doesn't work
   as well if you try to make a smaller portion. It will
   keep in good condition in the freezer but only for a
   few weeks. Remember to wrap it up well or your
   ice-cream may take on a strange taste!. A. Heat the
   oil in a heavy pan then add the chopped onion and stir
   for a few minutes with the heat on high B. Add the
   ginger, garlic, green chile, turmeric, cumin and
   coriander. Stir for 30 seconds then put the heat down
   to very low C. Cook for 20 minutes stirring from time
   to time making sure nothing browns or burns D. Take
   off the heat and cool a little. Put 4 fl oz cold water
   in a blender, add the contents of the pan and whizz
   until _very_ smooth. Add the passata and stir E. Put
   the puréed mixture back into the pan, add the salt and
   cook for 30 minutes over low heat stirring
   occasionally to stop it catching on the pan (you can
   add a little hot water if it gets too dry)
  
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