This satisfying salad can be made with the recipe for Double Roast Chicken or any other roast chicken and roasted vegetable leftovers.
In a small bowl, whisk together lemon juice and olive oil until combined. Season with salt and pepper; set the vinaigrette aside.
Arrange the salad greens, chicken, and vegetables on a dinner plate. Sprinkle with scallions and feta cheese, and drizzle with reserved vinaigrette. Serve.
White-wine vinegar may be substituted for the lemon juice.