Place 1 pound beets on a large piece of foil. Drizzle with 1 tablespoon olive oil and 3 tablespoons water; close into a packet. Roast at 400 degrees F until tender, 50 minutes. Peel the beets and cut into wedges. Whisk 1/3 cup orange juice, 2 tablespoons olive oil, and salt to taste in a bowl. Add 2 segmented oranges, the beets and 1/4 cup chopped toasted walnuts and toss.
Photograph by Antonis Achilleos