Toss avocado slices in one tablespoon lemon juice. Toss apple slices separately in the remaining tablespoon lemon juice. Toss grapes, walnuts, celery, apple, baby kale or arugula, and salt and pepper together. Carefully add avocado and toss.
Enjoy with a favorite clean eating salad dressing or vinaigrette served tossed in salad or on the side.