This healthy dish not only tastes great, but looks great as well. It perfectly highlights the fall colors: red, green, and orange.
Preheat oven to 400 degrees. Trim greens from beets. Cut off and discard stems.
Coarsely chop leaves and reserve. Wrap each beet in foil. Place beet packets directly on oven rack and roast until tender when pierced with a fork, about 1 hour. Cool and peel beets.
Cut beets into wedges and place in a medium bowl.
Cook beet greens in a medium saucepan of boiling salted water until tender, about 2 minutes. Drain and cool. Squeeze greens to remove excess moisture. Add greens to bowl with beets. Cut and peel skin and pith from oranges. Working over a bowl, cut between membranes to release segments. Add orange segments and any juice that has collected along with onion to beet mixture. Whisk vinegar, olive oil, garlic, and orage peel in a small bowl to blend; add to beet mixture and toss to coat. Season with salt and pepper. Let stand at room temperature 1 hour. Garnish with feta or goat cheese and walnuts.