This soup was inspired by a recipe that used pearl barley, leeks, beef broth, light cream and milk, and spinach, none of which I had on hand. I made substitutions using what I did have and modified to accommodate the longer cooking kale instead of the quick wilting spinach and ended up with an incredibly delicious soup. A funny thing happened though, my husband and I were happily slurping the soup up and we both came up with notion that the soup cried out for clams... next time.
One note about about farro, which is an ancient type of wheat* - be sure to use one that has been milled a bit to remove some of the bran (pearled) because unmilled wheat berries take forever to cook and seemingly never become tender. Of course, if you have pearl barley in your pantry, use that.
Celery Root Soup with Kale and Farro
1/4 cup farro
1/2 teaspoon salt
3 cups water
2 tablespoons butter
1 sweet onion, finely chopped
1 celery root, about 2 pounds untrimmed, peeled and diced
4 cups chicken stock
1 cup creme fraiche
1 bunch lacinato kale, stems and ribs removed, coarsely chopped
salt and fresh ground black pepper
Combine the farro, 1/2 teaspoon salt and water in a saucepan and bring to a boil. Reduce the heat to low, cover and cook until the farro tender but still has a little bite, about 45 minutes to an hour. Add the kale to the pan and continue to cook 10 or 15 minutes longer, until the kale is tender.
While the farro is cooking, melt the butter in a soup pot over medium heat. Add the onion and celery root and saute until the onion becomes translucent, 4 to 5 minutes. Add the stock and bring to a boil over high heat. Reduce the heat to low and simmer until the celery root is tender, 10 to 15 minutes. Remove from the heat and let cool slightly.
Roughly puree half of the soup and return it to the saucepan. Add the cooked farro and kale along with the cooking water to the soup. Stir in the creme fraiche and simmer the soup until hot. Season with salt and pepper to taste.
*There's lots of confusion about which ancient strain of wheat is used to make farro. Emmer, spelt, and einkorn are all candidates. Spelt seems to be the grain most often identified as THE farro, but other experts claim it's emmer. And other sources say that all three are made into farro. If you're curious, do a web search for farro and be prepared to be confused...