Tender white beans give this soup rich texture and substance, while crisp apples add natural sweetness. Celery root, also known as celeriac, is the knobby, rough root of the celery plant. Once peeled, its flesh has a creamy white color and the bright herbaceous flavor of celery.
Combine celery root, parsnips, apples, potato, onion, beans, bay leaf, thyme and 4 cups water in a large pot. Cover and bring to a boil over high heat. Reduce to a simmer and cook until beans and celery root are completely tender and falling apart, about 40 minutes. Remove bay leaf and purée soup until creamy using an upright or immersion blender. Add warm water as needed to reach desired consistency and continue to simmer. Serve with lemon wedges.
Per Serving:Serving size: about 1 cup, 130 calories (5 from fat), 0g total fat, 0g saturated fat, 0mg cholesterol, 190mg sodium, 29g carbohydrate (6g dietary fiber, 9g sugar), 5g protein