(Adapted from www.epicurious.com)
3 medium beets, with 1 inch of stems attached
1 small celeriac
1 tablespoon plus 1 teaspoon fresh lemon juice, plus additional to taste
1 tablespoon minced shallot
2 tablespoons olive oil
salt and pepper
¼ cup chopped walnuts, toasted and cooled
Preheat oven to 425° F. Wrap beets tightly in foil and roast until tender, about 1¼ hours.
While the beets roast, peel celeriac with a sharp knife and cut into thin slices. Then stack the slices and cut into 1/8-inch-thick matchsticks. Whisk together lemon juice, shallot, oil, salt, and pepper to taste in a large bowl until combined well, then add celery root and toss until coated. Keep at room temperature, covered, until ready to add beets.
Carefully unwrap beets and, when just cool enough to handle, slip off skins and remove stems. Cut beets into 1/8-inch-thick matchsticks and toss with celery root.
Let salad stand, covered, at room temperature 1 hour. Taste salad and season with more lemon juice and salt if necessary. Sprinkle with toasted walnuts. Serves 2.
NOTE: To toast nuts, spread them in a shallow baking pan in a 250° F oven until golden, about 15 to 18 minutes.