1. Preheat grill to medium-high heat (350° to 400°).
2. Combine balsamic vinegar and brown sugar in a small saucepan over medium heat. Bring to a boil, reduce heat to low, and simmer about 15 to 20 minutes or until vinegar is reduced to a glaze; set aside.
3. Brush fruit with olive oil, and sprinkle with salt and pepper. Grill fruit, in batches, 1 minute on each side. Transfer to a platter.
4. Drizzle grilled fruit with half of balsamic glaze. Top fruit with cheese, and drizzle with remaining balsamic glaze. Serve immediately.