A top sirloin is a cut of meat that comes from about the middle of the back region of an animal. Typically cut from beef, it comes from just below the tenderloin if picturing an animal standing upright. As a cut of meat, the top sirloin, or top loin, is typically considered to be better than the bottom sirloin, which is usually tougher and not as flavorful. A top sirloin can potentially be a very nice cut of beef, but it is not necessarily the most flavorful and is not quite as expensive or tender as the tenderloin.
The sirloin is, generally, the region of the cow near the back end but just before the hind quarters of the cow, often called the round. This entire region has the sirloin at the top, which is separated from the top loin by another cut of meat referred to as the tenderloin. Below the top sirloin is the bottom sirloin, which is a much lower quality cut of meat, and is much less tender than the top loin. A number of different cuts of steak can come from this region, including the French filet mignon or tenderloin steak, and the porterhouse steak.
Many butchers and steak lovers consider the porterhouse to be the finest steak cut available from a piece of beef. This cut includes two different muscles, with part of the steak being from the top sirloin and the other part being from the tenderloin. By including both muscles, the steak has the tenderness of the top sirloin and the deep flavor of the tenderloin. This type of steak is not typically marinated and often enjoyed cooked only to medium, or just below medium with some pink still on the inside.
Some American butchers refer to cuts of top sirloin as chateaubriand, though this is fairly confusing, since French butchers and chefs use the term to refer to a cut from the tenderloin similar to the filet mignon. The name sirloin comes from a derivation of an Old French word surlonge, which meant “over loin” or “above loin.” A number of legends have sprung up due to the nature of the word “sirloin” in English and its seeming similarity to the prefix “sir” used in English knighthood.
The most common story tends to be that the English king Henry VIII was so pleased when dining on a meal that he decided to knight the beef that he had enjoyed. Some legends indicate he dubbed the cut of meat “Sir Loyne of Beefe” and Samuel Johnson even mentioned this bit of apocrypha in his Dictionary of the English Language. Early written uses of the word, however, clearly spelled it surloin, which indicates its Old French roots, and not the more amusing etymological pun.