Francesinha

Francesinha is bread layered with ham, steak and sausage, smothered in melted cheese and a hot tomato-beer sauce. It is Porto's monumental answer to the croque monsieur, and the sauce alone can carry a full page of a menu's worth of guarded restaurant secrets.

What it really is

Two slices of bread hold a stack of thin steak, cooked ham and a smoked sausage, all pan-fried or grilled just long enough to warm through before a full blanket of cheese melts over the top under a hot broiler. The sauce that floods the plate is built on tomato and beer, sometimes fortified with a splash of port or whisky and a hidden mix of spices that varies by kitchen, simmered down until it's thick enough to pool rather than run straight off.

The sauce is the part every kitchen guards. Two francesinhas can look nearly identical and taste completely different depending on what goes into that tomato-beer base; it's the single detail regulars actually order by, more than the sandwich itself.

How it is served

• On a plate, drowned in sauce, often with a fried egg on top.
• With a side of fries for the sauce to pool into.
• As a full meal, rarely a light bite.

How to write it on the menu

• Flag the wheat in the bread, the dairy in the cheese, the egg if included, and the sulphites the sauce or beer may carry.
• Say if a vegetarian version replacing the meats is offered, since some kitchens do a version built around vegetables instead.
• Note that it's a substantial, knife-and-fork dish rather than something to eat by hand, since the sauce makes that impossible.

The ingredients, allergens and dietary notes listed here describe a typical recipe. They are not a binding declaration for any particular restaurant: recipes, portion sizes and the products used can differ.