The Sandwich Poulet Rôti is the roast chicken sandwich, skin and all, in the register of the Sunday bird and its leftovers. The defining element is a whole roasted or rotisserie chicken carved rather than a portion of cooked breast: dark meat and light, the crisp seasoned skin, the rendered fat and pan juices that come with it. Pulled or sliced off the carcass and laid into a split baguette, that mix is the sandwich, and the presence of skin and dark meat is exactly what separates it from a plain chicken baguette. The region is national, the everyday afterlife of a roast that turns up wherever chickens are roasted on a spit.
The craft is what the whole bird brings that a trimmed breast does not. Roasting renders the fat under the skin and concentrates the meat's savor, so the filling arrives already moist and already seasoned, the thigh meat richer and more forgiving than breast, the skin adding salt and a crisp counter-texture. Pulled by hand rather than cut, the meat keeps the irregular shreds and crisp edges that read as a roast rather than as deli slices. The fat does the lubricating that butter or mayonnaise has to supply in a plainer chicken sandwich, which means this one often needs neither, though a spoon of the pan juices or a little of the resting fat brushed onto the crumb deepens it without making it greasy. A fresh baguette with a firm crust braces the soft interior, and the sandwich is best while the chicken still carries some warmth, before the rendered fat sets and the skin loses its crispness. A spoonful of cool acidity, a few cornichons or a sharp mustard, keeps the richness in check.
Variations follow the leftover logic, more dark meat in one, the crisp skin saved for another, a little of the roast's lemon or garlic worked in, sometimes the cold chicken folded with a spoon of mayonnaise once the warmth is gone. The Sandwich Poulet Rôti sits next to the plain Sandwich Poulet it richens, and belongs with the roast-and-sliced builds the catalog groups under Baguette Rôti / Bœuf. Its specific contribution is the whole bird, skin and dark meat and rendered fat included, the chicken sandwich in its richest and least trimmed form.