Roast the Beets:

Preheat your oven to 400°F (200°C).

Wrap each beet in aluminum foil and place them on a baking sheet. Roast for about 30-40 minutes or until tender (you can check by inserting a fork).

Let the beets cool for about 10 minutes, then peel and slice them into wedges.

Prepare the Dressing:

In a mixing bowl, whisk together the olive oil, balsamic vinegar, Dijon mustard, salt, and pepper until well combined.

Assemble the Salad:

In a large bowl, combine the mixed greens, sliced beets, red onion, and walnuts.

Drizzle the dressing over the salad and gently toss to coat.

Top with crumbled goat cheese.

Serve:

Plate the salad and enjoy! It can be served immediately or chilled in the refrigerator for 10-15 minutes before serving.