The Sandwich Roquefort-Noix is the codified pairing rather than the cheese alone, and the walnut is not a garnish here but half the structure. Roquefort is the sheep's-milk blue from the Aveyron, cave-ripened with Penicillium roqueforti in blue-green veins, sharp and salty and creamy enough to spread at room temperature. The noix are walnut halves, bitter, tannic, and dry where the cheese is rich and wet. The build is a length of baguette, a thin spread of beurre demi-sel or none, the Roquefort crumbled or pressed into the crumb, and walnut halves set into it so every bite carries both.
The logic follows from the contrast the pairing is built on. Roquefort on its own is forward and one-directional: salt and piquancy and cream, with no internal counterweight. The walnut supplies what the cheese lacks, a bitter, astringent crunch that the blue leans into rather than fights, and a dry texture against the creaminess that keeps the sandwich from going heavy. This is why the two are a named pair rather than a cheese with something added: each covers the other's gap. The bread has to carry a firm crust to absorb the salt and brace the nuts, since a soft loaf goes slack under the cheese and offers nothing for the walnut to press against. A thin film of honey is the common third element, pulling against the salt and rounding the bitterness without softening either; it is optional, and the pair stands without it. It eats best at room temperature, where the cheese softens into the crumb and the walnut stays crisp.
Variations move along the cheese and the sweet element rather than off the pairing. A milder cow's-milk Fourme d'Ambert with walnuts reads gentler and rounder; a sharper, older Roquefort deepens the contrast; honey or a thin layer of fig pushes it toward the cheese-board end. For the cheese handled on its own terms the catalog treats those separately: see Sandwich Roquefort for the sheep's-milk reading and Sandwich au Roquefort for the cheese-dominant build. This entry stays on the pairing. The Sandwich Roquefort-Noix belongs with the cheese sandwiches the catalog groups under Baguette Fromage, the tradition that gives every regional French cheese its own treatment. Its specific contribution is the walnut as structural partner, a bitter dry crunch that completes a cheese with no counterweight of its own.