Walk into any café in Porto, Portugal, and you'll likely see one common thing on the menu: the Francesinha. This indulgent sandwich now has many variations, but they all include a stack of ham, steak, sausage, and cheese, covered in a tangy tomato sauce. It was invented in the 1950s at a Porto restaurant called A Regaleira, when a French customer asked for a croque monsieur. Francesinha translate to "little French lady" in Portoguese. We visit Cafe Santiago, who makes Francesinhas beloved by locals and tourists alike, to see how the iconic sandwich is made.