Final answer:
The porterhouse, a large bone-in cut, is sourced from the loin section of a cow and it includes parts of the top loin and tenderloin.
Step-by-step explanation:
The dry-aged porterhouse is a premium steak cut from the loin section of the cow. Specifically, the porterhouse includes meat from both the top loin and the tenderloin, separated by a T-shaped bone, which classifies this cut as bone-in. When referring to the size, the porterhouse is generally large due to its inclusion of two types of steak.The dry-aged porterhouse is cut from the loin. It is a large and bone-in cut.