The francesinha was invented in the 1960s by Daniel da Silva, a returned emigrant who reimagined the French croque-monsieur as a multi-layered fortress of wet-cured ham, linguiça, fresh sausage, steak, and melted cheese, then drowned it in a beer-and-tomato sauce spiked with piri-piri. The name translates to "little Frenchie," a wink at its Gallic ancestor, but the dish belongs entirely to Porto. It arrived during the city's post-war industrial boom, when riverside tascas fed shipyard workers and tile-factory crews who needed calories and speed. Today the francesinha anchors menus from Ribeira to Foz, each kitchen guarding its sauce recipe like a vault combination. A francesinha cooking class porto session deconstructs that alchemy. You start with the protein scaffold: thin-sliced steak pounded to tenderness, chouriço rings that release paprika oil under heat, linguiça links that snap when bitten. The bread matters—toasted white loaf, sturdy enough to hold structure under sauce but porous enough to soak. Cheese goes on in sheets, not shreds, so it forms a continuous blanket under the broiler. The sauce is where amateur cooks stumble: tomato paste, dark beer, bay leaf, whisky, stock, butter, and a chili paste whose proportions remain contested. Some chefs add brandy or port; others insist on garlic or mustard. The liquid reduces for thirty minutes, thickening into a glaze that coats the back of a spoon. Workshops unfold in working kitchens—historic taverns near São Bento station or residential flats in Cedofeita where instructors cook for their families. You sear meat on cast-iron griddles, layer the sandwich by hand, then watch it transform under direct heat. The cheese bubbles and browns at the edges. The sauce pools around the base, sometimes served in a shallow ceramic dish so you can dip bread or fries. Instructors demonstrate the final flourish: a fried egg on top, yolk still soft, or a crown of crisped presunto. The result weighs close to a kilogram. You eat half, then understand why locals order one francesinha between two people and a beer to cut the richness. The dish is engineering as much as cooking—a deliberate construction that turns inexpensive cuts into something dense, savory, and unambiguous.