Preheat oven to 350 degrees F. Coat a 12-cup Bundt pan with cooking spray.
In a medium bowl, combine bacon, Parmesan cheese, and onion; set aside.
Cut each biscuit into quarters. Dip one-third of biscuit pieces into melted butter, and place in prepared Bundt pan. Sprinkle with half of bacon mixture. Repeat layers with remaining biscuit pieces and bacon mixture, ending with biscuit pieces.
Bake 40 minutes, or until golden. Cool in pan 10 minutes; invert onto a serving platter, and serve bread immediately.