01 - Preheat the oven to 400°F. Wrap each beet individually in foil, place on a baking sheet, and roast for 40-45 minutes, or until tender when pierced with a knife. Let cool slightly, then peel and cut into wedges or cubes.
02 - While the beets roast, toast the walnuts in a dry skillet over medium heat for 3-4 minutes, stirring frequently, until fragrant. Set aside.
03 - In a small bowl, whisk together olive oil, balsamic vinegar, Dijon mustard, honey, salt, and pepper until well combined.
04 - In a large bowl, combine the salad greens, roasted beets, red onion, and toasted walnuts. Drizzle with the dressing and toss gently to coat.
05 - Transfer the salad to a serving platter or individual plates. Top with crumbled feta and sprinkle with fresh parsley. Serve immediately.