To make the vinaigrette, in a jar or small bowl whisk together the balsamic vinegar, avocado or olive oil, honey, salt and pepper. Whisk in the orange juice concentrate, and set aside or store in the refrigerator if preparing ahead.
Place the salad greens in a large bowl, and toss with enough dressing to lightly coat. Distribute to individual salad plates. To the same bowl, add the chopped beets, walnuts, and goat cheese or feta. Drizzle with enough of the vinaigrette to lightly coat, and toss well. Mound the beet mixture on top of the greens on the individual plates. Serve with additional vinaigrette, if desired, refrigerating the remaining amount for future use. (For the full recipe, I use slightly less than 1/2 cup of the vinaigrette; but coat to your liking.)
Conversely, you may toss everything together in a large bowl. The first method, however, will ensure a perfect combination of the beets, nuts, and cheese. With a large bowl, the add-ins have a tendency to sink to the bottom.