Leek and potato soup

http://www.recipesource.com/text/soups/soups/recipe2295.txt -

                      *  Exported from  MasterCook  *
 
               Creamy Leek and Potato Soup (Pressure Cooked)
 
 Recipe By     : Cooking Under Pressure by Lorna J. Sass; copyrighted 1989
 Serving Size  : 1    Preparation Time :0:00
 Categories    : Soups And Stocks
 
   Amount  Measure       Ingredient -- Preparation Method
 --------  ------------  --------------------------------
    4      tablespoons   butter
    6      medium        leeks, white part only (abt 4 c) -- thinly sliced
    3      stalks        celery -- thinly sliced
    3      large         potatoes (abt 1 1/2 lbs), scrubbed -- cut in 1/4″ slice
 s
    5      cups          vegetable or chicken stock
      1/4  cup           finely minced fresh dill -- optional
                         salt and pepper -- to taste
 
 serves 6
 
Heat the butter in the cooker. 

Saute the leeks and celery for 2 minutes, stirring occasionally.

 Meanwhile, cut the potato slices in half. 

Add the potatoes  and stock. 

Lock the lid in place and over high heat bring to high pressure. 

Adjust heat to maintain high pressure and cook for 5 minutes. 

Let the pressure drop naturally or use a quick release method. 

Remove the lid, tilting it away from you to allow any excess steam to escape.

Puree half of the soup in a blender or food processor. 

Pour the puree back into the pot. 

Stir in the dill (if desired) and add salt and pepper to taste. 

Reheat thoroughly and serve.
 
 Variation:  For a creamier, more elegant version of this rustic country dish, puree the entire mixture, but don't overprocess or the potatoes will become gummy.