A Challah Sandwich (כריך חלה) is the assembled sandwich built on slices of braided egg bread: the loaf turned into a soft, slightly sweet vehicle for a filling rather than served as bread alongside a meal. The angle is the match between a tender, enriched, faintly sweet crumb and what goes between the slices. Because challah is softer and richer than a standard sandwich loaf, this build only really works when the filling is chosen to suit it. The successful versions lean into the sweetness and softness; the failures fight it, and the bread loses every time.
The build is slice, support, fill, close. The bread is cut thick, since a thin slice of such a tender crumb collapses under any spread, and slightly stale or briefly toasted challah is often better than fresh because a firmer slice resists a wet filling. A thin barrier of butter or a soft cheese on the cut faces helps slow moisture from reaching the crumb. The classic fillings are the soft, rich, mildly sweet ones that the bread flatters: egg salad, tuna salad, soft cheese with cucumber, smoked salmon, sometimes a simple cold roast chicken or honey-touched spread. The sandwich is built with the wetter element kept off the bare crumb where possible and the slices pressed gently so it holds without crushing. Done well, the slice keeps its shape, the faint sweetness of the bread frames the filling, and the whole thing eats soft but intact. Done badly, the bread is too fresh and pulps the instant the filling touches it, the filling is something sharp or structural that clashes with the sweet crumb, or it is so overfilled that the tender bread tears apart on the first bite.
Within this build the variation is in the filling and the treatment of the bread. Egg salad and tuna salad are the workhorses; smoked fish with soft cheese is the upscale reading; a thin layer of jam or honey with butter turns it toward a sweet sandwich entirely. Sliced thick and griddled it firms and caramelizes into something closer to a French-toast sandwich, a warm relative worth its own article. The bread itself, the braided loaf and what makes it a particular choice of base, is documented separately; this entry is about what happens once it becomes a filled sandwich. On its own terms, the challah sandwich is an exercise in matching: pick a filling soft and rich enough to belong with the bread, manage the moisture, and it becomes one of the more generous and comforting sandwiches in the Israeli repertoire.