Top Sirloin Cap On Steak This page first published: Feb 16, 2004 · Updated: Jun 12, 2018 · by CooksInfo. Copyright © 2021 · This post may contain affiliate links · This blog generates income via ads · A Top Sirloin Steak with the “cap” left on, the cap being a boneless, triangular piece of meat with fat that is a little chewier than the rest of the Top Sirloin Steak. Cooking Tips Dry heat cooking.