Remove the seeds from the pomegranate. Reserve half the seeds for garnish, place the others in a fine mesh strainer set over a salad bowl. Use the back of a spoon to squeeze the juice out of them. Discard the crushed seeds. Whisk the oil, lemon juice, honey, cumin, cayenne, salt and pepper into the pomegranate juice. Mound the spinach on 4 salads plates. Decorate the top with pears, walnuts and the reserved pomegranate seeds. Drizzle with the vinaigrette and serve.