In small glass bowl, prepare salad dressing first and set aside. Use salad spinner to remove excess moisture from the greens.
In large non-reactive serving bowl place the sliced apples and toss them with a little bit of apple cider to halt oxidizing. Next, add the salad greens, a few tablespoons of the salad dressing and toss gently again with tongs to mix.
Serve remaining salad dressing on side along with the toasted walnuts if using. For best results, cut up apples and toss with the vinegar right before serving.