Preheat the oven to 350 degrees. Shave a little off the fat end of the pear so it stands up tall. Core it from the base up if you wish using an apple corer or a thin spoon. Leave the stems on. Place the pears on a baking sheet and brush with agave nectar. Roast until the pears are tender and browned -- anywhere from 20 to 45 minutes depending on the size and degree of ripeness when you started. Whisk all the dressing ingredients together. Toss the greens with dressing in a large bowl and scatter them artfully on the plates. Place a pear in the center of each. Sprinkle with optional pomegranate seeds (check the last recipe for instructions on how to seed a pomegranate).