One Alpine cheese does all the work here, and the bread is asked for little beyond a crust to hold it. Beaufort is a firm cooked-curd mountain cheese from Savoie, made from the milk of high-pasture herds, dense and sliceable with a fruity, almost brothy depth and a faint note of hazelnut that sets it apart from the softer cheeses of lower country. The build is a split crusted loaf, a thin spread of butter, and a thick layer of Beaufort cut into slices rather than crumbled. What lifts it past a generic cheese sandwich is the cheese itself: firm enough to hold its shape against the crumb, complex enough to carry the whole sandwich without a second loud ingredient.
The logic follows from the curd. Beaufort is pressed and aged dense, so it does not weep or smear; it holds in clean slices that scale to the bread the way a sliceable cheese should, layering predictably and giving each bite the same proportion. Its depth is savoury and long rather than sharp, which sets the constraint: pile on a strong cured meat or a pungent condiment and you flatten the cheese's quieter, brothy character instead of presenting it. The successful version stays close to bare, a good crust and the cheese sliced thick enough to taste, maybe butter to bridge the wheat to the curd, perhaps a few bitter walnuts or a leaf of frisée for contrast. The bread needs a real crust because the cheese brings no acid and no crunch of its own; the cheese needs to be at cellar temperature rather than fridge-cold, because cold mutes the fruitiness that is the reason to make this sandwich.
Variations stay on the Alpine cheese shelf rather than wandering off it. The same loaf takes a thin sliver of air-dried mountain ham laid alongside the cheese, or a young Comté swapped in for a milder, nuttier register, or a Tomme de Savoie for something earthier and softer. Each is a swap of one mountain element for another, the bread and the restraint held constant. The Sandwich au Beaufort sits among the regional-cheese sandwiches the catalog groups under Baguette Fromage, the long rack where each French cheese gets its own treatment. Its specific contribution is a dense, fruity, cooked-curd Alpine cheese that carries the sandwich on its own and wants the rest of the build to stay quiet.