Make the vinaigrette:
In a jar with a tight-fitting lid, combine the olive oil, vinegar, port, honey, and the ¼ teaspoons of salt and black pepper, and shake vigorously until emulsified. Taste for seasoning, adding more salt if needed.
Pour 3 tablespoons of the vinaigrette onto a shallow plate and reserve the remainder.
Divide the salad greens among six plates.
Cut each pear in half and remove the core.
Dip the cut sides in the plated vinaigrette. Set up your grill for direct grilling.
Grill the pears, cut sides down, until light grill marks appear, about 5 minutes.
While the pears are still warm, arrange a pear half on each salad plate, cut side up, and put a dollop of mascarpone in each cavity.
Drizzle with the reserved vinaigrette (shake the jar if necessary), and top with the toasted macadamia nuts and pomegranate seeds, if using.