In a 3-1/2 to 4-quart slow cooker that has been sprayed with cooking spray, mix the beef, onions, broth, vinegar and bay leaves. Cover and cook on low for 7 to 9 hours.
About 15 minutes before serving, cook the noodles as directed on the package. Remove the bay leaves from the beef mixture. Stir in the crushed cookies and brown sugar.
Cover and cook on for 15 minutes longer or until mixture is bubbly and thickened. Serve beef mixture over noodles; sprinkle with the parsley. Serves 6.