From the picture below (pictures five and six show it as well) you can see where the tenderloin becomes smaller. It tapers from back to front with the Porterhouses starting near the Sirloin.
The most common question I get asked from customers is, "What is the difference between the T-Bone and Porterhouse?". The answer is fairly simple. The Porterhouse has a tenderloin (at least more than one or two bites) and the T-Bone does not. While many grocery stores and restaurants usually refer to all of the cuts off of the Short Loin as T-Bones, this is not true. This is a common practice as to keep confusion and questions to a minimum.
First off, I always recommend using/buying the best quality meat you can find. At my market, we use "USDA Choice" beef for many reasons. Two main reasons are, it is not outrageously expensive compared to "USDA Select". Also, it is consistently marbled for flavor and tenderness but not outrageously marbled (USDA Prime) so as not to scare off any nitpickers. Below is a whole Short Loin in a cryovac package. It is not easy to see in the pic but it has US regulations, USDA and the originating company stamps on it as proof of quality.
Here is a picture of what the Short Loin looks like directly out of the package. You can see a heavy fat cover called Suet (pronounced soo-it). Suet has many purposes that I will explain in greater detail in a future entry.
The side facing the camera is the Porterhouse or Loin end. It sits rearward on the beef.
This is what the Short Loin looks like without the heavy fat cover. You can see the tenderloin on top as well as the last rib (the smooth line at the opposite end from the camera).
Another shot of the whole Short Loin. This time it is ready to cut.
Notice on this shot how the tail (farthest cut to the left), Chine Bone (top cut on right side) and the face (cut exposing the first cut, in this case, a Porterhouse) have been trimmed. It is now very clear the two individual cuts used in processing T-bones and Porterhouses. They consist of the Tenderloin on top, The Loin Strip on bottom with a bone separating the two.
Here two Short Loins have been cut and separated into two piles. Porterhouses on the left, T-Bones on the right. Typically, each steak is cut between 3/4 and 1 inch thick. Once the steaks have been cut and separated, they will be trimmed to market spec. I tend to keep about 1/4-3/8 inch fat trim on the steaks. This will define the outside edges of the steak while adding flavor.
Here are two rows of trimmed T-Bones. You can see in the picture that I have the steaks, trim pile, fat pile and a Meat Comb. The trim pile is added to other trim piles and ground into hamburger. The fat pile is discarded and the Meat Comb is used to remove the residue, leftover from the saw blade, from the steaks. The two pictures below are the same except for the lower one has not had the steaks combed. Look closely and they will appear to be fattier and lighter in color. Basically the residue is to meat what sawdust is to wood.
This picture is essentially the same as the two previous with the exception that these are Porterhouses and not T-Bones.
This last picture is aimed at the discerning meat buyer. Behold, three Porterhouses. On top we have a first cut Porterhouse. Usually bigger than the rest, making it a must-have in the "bigger is better" crowd. While it does have marbled fat and a large tenderloin, the strip side has what we call a "Vein Cut" Look at the top of the steak and you will notice an almond shaped piece of meat that is not present on the other two steaks. This large piece of sinew is not necessarily bad. However, paying market price for one isn't necessarily good either.
The second steak is the best of the bunch. It has a large tenderloin and the fat is nicely marbled. Most importantly, it is not a Vein Cut. Typically it takes three to four 3/4 inch cuts to get past the vein cuts.
The last cut in the picture is also a Porterhouse...but just barely. It does have some tenderloin but doesn't impress the way the previous cuts do.
If you want them thicker or thinner, your butcher will gladly make it happen. If this isn't the case, find another butcher.
Tips for grilling: Set grill on high. Seer both sides of the steak for 60-90 seconds. Turn heat down between low and medium. Flip your steaks every three to four minutes. Depending on your grill, this could take anywhere from 15-25 minutes to complete.
Most importantly, do not leave them unattended. Few things in life are worse than burning a great steak because you didn't keep a close watch on them.