2 lb. leeks, white & light green part only,
washed & chopped
2 lb. russet potato, peeled and chopped
3 Tbs. butter
2 bay leaves
salt & white pepper
water

Melt butter in a large soup pot over medium heat. Add leeks and cook until limp, about 8 to 10 minutes. Add potatoes, bay leaves, a pinch of salt and pepper, and enough water to just cover. Bring to a boil. Reduce heat to a simmer.
Cover and cook until vegetables are tender. Remove bay leaves and puree until smooth. Season to taste.