Preheat your grill to medium high heat. In a large bowl combine broccoli florets, onion, olive oil, salt and pepper. Place into a large grill wok or basket. Carefully place onto hot grill and close lid. Let cook for about 5 minutes. Using tongs, gently toss and close lid again, cooking for another 7-10 minutes or until broccoli and onion start to char. Onions will soften and broccoli will be crisp tender. Cook longer to your preference. Place in a serving dish and top with toasted pine nuts and lots of freshly grated Parmesan cheese. Optional: Drizzle with additional olive oil and sprinkle with red pepper flakes.