Peel 3 medium red beets and cut them into 1-inch cubes. Toss the beet cubes with 2 tablespoons olive oil and 1/2 teaspoon salt in a mixing bowl. Spread the seasoned beets in a single layer on a baking sheet lined with parchment paper. Roast the beets at 400°F for 35-40 minutes until fork-tender and slightly caramelized at the edges.
Remove the roasted beets from the oven and let them cool for 15 minutes to room temperature.
While beets cool, whisk together 3 tablespoons olive oil, 2 tablespoons balsamic vinegar, 1 teaspoon honey, and 1/4 teaspoon black pepper in a small bowl.
Place 5 cups fresh arugula in a large salad bowl.
Add the cooled roasted beets to the arugula.
Pour the prepared dressing over the salad ingredients. Gently toss everything together until evenly coated.
Sprinkle 1/2 cup crumbled goat cheese and 1/3 cup chopped walnuts over the top.