Preheat oven to 400 degrees. Trim sprouts from the stalk and cut in half. In a large bowl, toss sprouts with 1/4 cup Garlic olive oil, Garlic sea salt and pepper. Add more oil if needed to throughly coat. Add plain sea salt if desired. Place sprouts on baking sheet face down and roast for 20-30 minutes or until softened and browned on the bottom. Top leaves of sprouts will also brown and dry resembling parchment paper which adds to the texture and taste of the dish, although be careful not to burn sprouts. Transfer to a bowl.
Place chopped leeks on same baking sheet along with chestnuts. Toss with remaining oil, sea salt and pepper to taste and roast for 15 – 20 minutes or until leeks are soft and just start to caramelize. Meanwhile, in a heavy skillet, cook bacon until crisp and let drain on paper towels.
Toss sprouts with leak-chestnut mixture and add pomegranate seeds. Transfer to serving dish or platter and drizzle with Fig balsamic vinegar. Top with crumbled pancetta. Serve.