Combine the apples, spinach, endive, walnuts and blue cheese in a large bowl. Add the vinaigrette, toss to coat, and season with salt and pepper, to taste.
Whisk together the pomegranate molasses, vinegar, mustard, honey and salt and pepper in a medium bowl. Slowly whisk in the olive oil until emulsified. Vinaigrette can be stored, covered tightly, in the refrigerator for 2 days.