Divide the meatball mixture into 4 equal portions. Divide each portion in half. Form 6 equal-sized balls out of each of the 8 portions. Make sure to press the balls together firmly. Roll each ball in remaining breadcrumbs, and place on a lightly oiled baking pan. Spray meatballs lightly with pan spray, and place in the preheated oven for 20 minutes or until browned on the outside and just-cooked in the center.