Preheat oven to 400°F (200°C). Wrap beets individually in foil.
Roast beets for 45-60 minutes, or until tender when pierced with a fork. Let cool slightly.
Once cool enough to handle, peel the beets and cut into bite-sized cubes.
While beets are roasting, prepare the vinaigrette. In a small bowl, whisk together olive oil, red wine vinegar, Dijon mustard, honey, salt, and pepper.
In a large bowl, combine the cubed beets, crumbled feta cheese, toasted walnuts, and chopped parsley.
Pour the vinaigrette over the salad and toss gently to combine. Serve immediately or chill for later.
Notes
This salad can be made ahead of time. Store the components separately and toss with the vinaigrette just before serving to prevent sogginess.