A lot of fall flavor is packed in this super simple recipe for Celeriac (Celery Root), Potato, Apple and Parsnip Soup. Made with ingredients from the last installment of my CSA, this soup is so easy that I cooked it from start to finish while on a webinar for food bloggers hosted by Sara Kate Gillingham-Ryan, editor extraordinaire of TheKitchn fame. Subtle celery, tart apple, mild starchy potato and bitter parsnip -- the flavor combo is divine and the soup is low calorie to boot (about 200 calories per cup).
It's important to peel all the vegetables to get a nice white soup. It's much easier to use a paring knife than a vegetable peeler to trim away the outer skin of the celery root.
After the leek and onion are translucent, it only takes 20 minutes for the celeriac (celery root) and other veggies to soften in the simmering stock.
Before moving the cooked veggies to my Vitamix blender, I let the veggies cool. I've found that working with cool soup is far less hazardous than exploding hot liquid erupting from the food processor or blender (been there done that). I also set aside some broth from the pot before spooning the veggies into the carafe. It's much easier to add broth to a too thick soup than take it away if the puree comes out too thin. I ladled the excess broth to the whirling blender a few ounces at a time. "Parfait" (which means perfect in French) -- not to thin and not to thick. Depending on the size of your blender or food processor, you may need to puree the soup in batches. Reheat when ready to serve.
Simple Celery Root, Potato, Apple and Parsnip Soup
1 pound trimmed celery root
1/2 pound potatoes, such as Yukon gold, peeled
1/2 pound tart apples, peeled
1/4 pound parsnip, peeled
1 leek, diced
1 small onion, diced
3 Tablespoons sunflower oil, olive oil or butter
4-5 cups of vegetable or chicken stock, preferably homemade (in a pinch I use Penzey's Soup Base and Seasoning)
Salt and pepper to taste
Suggested garnish: Paprika, fresh herbs, dried thyme
Chop the peeled vegetables (celery root, potatoes, apples and parsnips) into equal size 3/4" cubes. Set aside. Heat oil in the bottom of a stock pot and saute diced leeks and onion over mediium heat until tender. Add the vegetables and just enough homemade stock to cover them. Put the lid on the pot and simmer for 20 minutes. Puree using an immersion blender or carefully in a blender or food processor (the liquid is hot) until creamy and smooth. Serve. Add salt and pepper and other suggested garnishes.