Trim the
outer leaves from the Brussels sprouts and cut a cross in the stems.
Boil or steam for 10 minutes, or until tender. Drain, cut in half and
place in an ovenproof dish. Drizzle with the melted butter and toss
gently to coat. Heat the oil in a pan, add the chopped onion and cook
over medium heat for 5 minutes. Stir in the bacon and cook for 5
minutes. Remove from the heat and place the mixture in a bowl. Combine
the breadcrumbs, parsley and 2 tbsp of the Parmesan with the onion
mixture. Season with freshly cracked black pepper. Spoon the breadcrumb
mixture over the Brussels sprouts and sprinkle with the remaining
Parmesan. Cook under a preheated hot grill for 5 minutes, or until the
top is lightly browned. Serve hot.