4 tbsp. unsalted butter
2 1/2 cups chopped leeks, white and light green parts only (3-4 med leeks)
1 1/2 pounds carrots, peeled and diced
1 med rutabaga, peeled and diced
8 cups chicken stock
1 1/4 cup creme fraiche or plain yogurt
heat butter in a large, heavy pot (with a lid) over medium-high heat
when melted and hot, add leeks, carrots, and rutabaga.
saute vegetables until softened, for 10 min or longer.
add stock and bring mixture to a simmer.
reduce heat, cover,
and simmer until vegetables are very tender, for about 30 minutes.
puree the soup in batches in the food processor or blender,
and return to pot (or use immersion blender to puree in pot).
I liked to leave the soup a little chunky and not fully pureed.
whisk in 3/4 cup of the creme fraiche or yogurt.
taste soup and season with salt and pepper, as needed.
to serve, ladle soup into bowls and garnish with a dollop of creme fraiche and a sprinkling of parsley if you like.