This might just be the perfect soup for a snowy winter's day. Eat with a handful of vegetable chips and you won't want anything else.
It's a no-fuss recipe we originally developed when my older son began chewing on vanilla beans. I realized we needed a way to sate his passion for vanilla without panna cotta, ice cream, or cookies.
If you want to let your kids get in on the action: little ones can scrub the parsnips, wash out the leeks, and put everything in the pot. We cool the soup before blending, then my boys put the soup in our food processor and whizz the ingredients all together. I don't trust them, however, to salt "to taste". —PassTheKnife
Prepare the vegetables. Remove the end of each parsnip, then scrub their skins and wash under water. Cut off the dark green leaves of the leeks and cut each lengthwise. Then, thoroughly rinse the white and light green parts to remove all the grit lingering between their layers.
Get the soup started. Heat butter in a large soup pot over a medium flame. Add the leeks, browning them. Slice open a vanilla bean and scrape out its seeds. Then add all parts of the vanilla bean, parsnips, white wine, bay leaf, and thyme to the pot. Add 4 cups of water to the pot, cover it with a lid and bring it to a boil.
Turn down the heat to reduce the pot to a simmer. And let it cook for 45 minutes.
Puree the entire contents of the soup, either in batches with a food processor or with an immersion blender.
To finish the soup, add cream, milk, and additional water, if needed. Then add salt and pepper to taste.
Don't forget the vegetable chips on the side. Their crunch is to the cream soup, like walnuts are to Rocky Road.