Cream Of Potato Soup
["1 1/2 c. sliced onions", "4 Tbsp. butter or margarine", "4 c. diced potatoes", "4 c. chicken broth", "1 tsp. salt", "1/8 tsp. white pepper", "1 bay leaf", "1 stalk celery", "1 egg yolk", "1 c. light cream (half and half)"]
["Saute the onions in butter for 5 minutes.", "Add the potatoes. Cover and cook over low heat for 5 minutes.", "Add broth, salt, pepper, bay leaf and celery.", "Cover and bring to boil.", "Cook over low heat for 30 minutes.", "Discard bay leaf and celery.", "Puree soup through electric blender or force through sieve."]
["onions", "butter", "potatoes", "chicken broth", "salt", "white pepper", "bay leaf", "celery", "egg yolk", "light cream"]