Potato-Leek Soup

I've been making this healthy version of "Vichyssoise" for years.  It couldn't be easier and very tasty.  You'll never miss all those calories.  If you feel like you want to "fatten" it up, you can easily add some cream at the same time you add the stock and whisk in some butter at the end.

2# Yukon Gold potatoes, peeled and cut into equal sized pieces
4 leeks, cut down white part only, washed and sliced thinly
1 large onion, peeled and sliced thinly
2 stalks celery, washed and sliced thinly
2 Tbsp. olive oil
1 qt. Beef stock (can use chicken as substitute)
3 Tbsp. fresh thyme, minced
salt and pepper, to taste

Place a large soup pot over medium high heat.  Add oil and allow to get hot.  Add leeks,onions, and celery reduce heat and sweat vegetables until tender about 10 minutes.  Do not allow vegetables to brown.   Add potatoes and mix.  Add stock and thyme, increase heat and bring to a boil.  Immediately reduce heat and simmer soup until potatoes are tender (10-15 minutes).  Very carefully puree soup in blender.  This will need to be done in small batches.  I like to remove about half of the potatoes before I puree the soup and cut them into bite sized pieces.  After I puree the soup, I return them back in to the mixture. It makes for a more chuncky soup.  Correct seasoning with salt and pepper.  Serve and enjoy!