This century-old restaurant is full of fresh beef, but its most famous plate isn't steak. People seek it out instead for a dish of aged lamb called the mutton chop. This is Keens Steakhouse ...

Plus no museum has ever served us a massive, majestic mutton chop. Over the past 140 years ... The burger at Keens is made with steak trimmings, which lend it a light dry-aged funk.