Leftover roast chicken rarely reheats into anything worth eating on its own — the microwave turns it rubbery and the oven dries it out. Chopped and folded into a chicken salad sandwich, though, it becomes something you'd actually make on purpose. This is the lunch for the half-eaten rotisserie bird sitting in the fridge, or the leftover breast meat from Sunday's roast.

It works because everything is sized and timed for a sandwich. Small, even pieces of chicken coat fully in the dressing, so the filling holds together in one stable layer instead of shedding chunks onto the plate. The dressing is seasoned to cut richness — Dijon's sharpness and lemon's acidity keep the mayo from tasting heavy — and the celery stays in small dice so you get crunch without biting into a raw chunk.

Expect a creamy, crunchy, tangy filling that tastes better the longer it sits. One batch fills four generous sandwiches and keeps 3 to 4 days in the fridge, so make the full amount even if you're only eating two today. The leftovers are the point of this one.