In a bowl, add your meat, parmesan cheese, egg, bread crumbs and salt n pepper to taste and mix all ingredients together with your hands.
Cut your onion in half, top to bottom. Separate each layer, creating cups and lay out. Take 1/3 C of the mixture and add it to each cup, 4 in total or 8 smaller onion bowls if making an appetizer size. Cover the bowl with a matching onion bowl and wrap 2 pieces of bacon around the enclosed onion bowl, covering the onion completely.
Place each covered onion in a cast iron skillet and bake 40 minutes and remove from the oven, add bbq sauce and bake another 10 minutes.