Earthy textures make this salad as interesting to look at as it is to eat. French lentils are firmer than many other varieties, so they won't get mushy or break apart as they simmer. Don't be turned off by the gnarled appearance of celery root. Once caramelized, the vegetable's citrusy, licorice-like flavor shines.
Combine celery, fennel, sunchokes, celery leaves, walnuts, and apples with a mustard vinaigrette for a nutritious side dish.