Preheat your oven to 400°F (200°C). Scrub, peel, and chop the beets into bite-sized pieces. Spread them on a baking sheet.

Drizzle the beets with olive oil and salt. Roast them for 25–30 minutes until fork-tender.

Toast the walnuts in a dry skillet over medium heat for 3–5 minutes until fragrant.

In a medium bowl, whisk together olive oil, balsamic vinegar, Dijon mustard, honey, salt, and pepper until emulsified.

In a large salad bowl, combine arugula and half of the dressing; toss to coat.

Add roasted beets, feta, red onion, avocado, and walnuts on top of the arugula.

Drizzle remaining dressing over the salad. Toss gently to combine or serve dressing on the side.