1. Preheat grill, or preheat oven to 400 degrees F.
2. Cut a 1/2-inch-thick slice from the top of each onion and discard. Trim just enough from bottoms for onions to stand upright. Remove the dry skin and the outermost layer of each onion. Use a paring knife and a spoon or an ice cream scoop to remove the inner layers of the onion, forming a bowl about 2 to 3 layers (3/8 inch) thick. Dice the removed inner section of one of the onions and set aside. Save remaining sections for another use or discard.
3. Prepare the stuffing. Heat 1 tsp. of the oil in a large nonstick skillet. Add reserved diced onion and bell pepper and saute just until tender, about 4 to 6 minutes. Add garlic, fennel seeds, and chili flakes and saute for about 30 seconds, until fragrant. Add turkey, stirring to crumble the meat, and saute until browned, about 6 to 8 minutes. Stir in the basil and salt. There should be about 2 cups of turkey stuffing.
4. Divide the turkey mixture evenly into each onion bowl, about 1/2 cup in each, mounding it up. Drizzle 1/4 tsp. of the remaining olive oil on top of each filled onion. Wrap each onion in two layers of aluminum foil and grill, covered, or bake in oven about 30 to 35 minutes, until onions are just tender.
5. Unwrap onions and transfer to a serving plate. Serve hot.
Source: fresh magazine July, August 2010