Query: What specifically how does Louis' Lunch cooks its' food?
Context: Though fiercely debated, the restaurant's founder Louis Lassen is credited by the Library of Congress with inventing the hamburger and steak sandwich. Louis' Lunch broils hamburgers, steak sandwiches and hot dogs vertically in original antique 1898 cast iron stoves using gridirons, patented by local resident Luigi Pieragostini in 1939, that hold the meat in place while it cooks.