Mix all ingredients except Singles just until blended. Fold 2 (30-inch-long) pieces of Reynolds Wrap® Aluminum Foil lengthwise in half twice. Crisscross pieces on work surface. Top with meat mixture; shape into 8-inch round loaf.
Use foil handles to gently lower meatloaf into slow cooker sprayed with cooking spray, extending ends of foil strips over edge of slow cooker; cover with lid.
Cook on HIGH 4 hours or until meatloaf is done (160ºF). Top with Singles. Let stand, covered, 5 min. or until Singles are melted. Use foil handles to remove meatloaf from slow cooker before slicing to serve.