Put the chicken stock, potatoes, leeks, celery
, bay leaf and thyme
in a large pot and sprinkle with salt and pepper. Boil until the potatoes are soft, 15 to 20 minutes.
Remove the bay leaf
. Using an immersion blender
(or in batches in a blender or food processor
), blend the soup until smooth. Pour the soup
into a medium pot; add the cream and simmer
until the soup has thickened, about 20 minutes.