Lunch at Casa Guedes is one of our favorite culinary rituals in Porto: After snagging a seat at the bar during the midday rush, we sit, mesmerized, as Mr. Cesar nimbly cuts slices of roasted pork shank, then places them on bread and moistens it all with his secret sauce. While not the only item on the menu, the famous sande de pernil (roast pork sandwich) is Casa Guedes’s raison d’être. After taking in Mr. Cesar’s entrancing sandwich-making choreography, we order the upgraded version of the sande, which is topped with gooey queijo Serra da Estrela, a creamy sheep’s milk cheese. Seating at this humble and low-cost eatery used to be minimal, and Casa Guedes’s popularity had long outstripped its capacity – fans could be found waiting patiently in queues stretching down the block.

A gloppy, meaty, cheesy brick served in a pool of sauce and with a mountain of fries: please meet the francesinha, the culinary pride and joy of the city of Porto. Today, restaurant billboards proclaim in many languages that they serve the best version in the world, revealing the genuine power of this artery-clogging combination that, incredibly, was originally conceived as a snack. We have to say it though: eating a francesinha is worth every last calorie. This dense sandwich, which is impossible to eat just with your hands, is often considered the lusophone version of the croque monsieur.

There has always been a bit of a rivalry between the two main cities of Portugal, Lisbon and Porto, which is well illustrated by an old running joke among some tripeiros (the name given to the people of Porto): whenever someone asks what is the best thing about Lisbon they will reply, “The highway sign that says ‘Porto.’” But it’s a healthy rivalry for the most part – football aside. Lisboetas, Lisbon locals, in general even tend to recognize that the food might actually be better in Porto and its surroundings, especially traditional dishes. While Porto does not benefit from the same multicultural influences that helped shape Lisbon’s restaurant scene, it is home to some very talented cooks with a knack for doing so much with so little.