If the pressed sandwich has a default, this is it. The ham and cheese hot sando is the classic kissaten item, the version that anchors the food menu at Japan's older neighborhood coffee houses and the one most people picture when they hear the word. It takes the sealed-pocket format from the baseline hot sando and fills it with the most forgiving possible combination: a slice or two of ham and a layer of cheese between thick soft bread, pressed until the edges crimp shut and the outside toasts. Its enduring place on kissaten menus comes from how completely the format and the filling suit each other.
This is the build that shows what the press is for. Cheese is the engine. Under the closed iron it melts into the warm ham and binds the whole interior into one cohesive, gently elastic mass rather than two separate cold layers, so a clean cut pulls a short, glossy thread. The ham contributes salt and a faint smokiness and, because it is thin and already cooked, it warms through fast, which is why this version needs the least time in the press of any in the family and is the one a busy kissaten counter can turn out quickly. Good shokupan toasts to a sweet lacquered crust that plays against the salty melt inside. The failure modes are simple. Too little cheese and the sandwich is just warm bread and ham with nothing holding it together; too much and it floods the seal and fries on the plate. Rush the press and the cheese never fully melts, leaving a rubbery slab instead of a molten center. Done right, it cuts cleanly on the diagonal, steam comes off the cut face, and the cheese is liquid edge to edge.
Because it is the baseline savory build, the variations are mostly small honest additions rather than reinventions: a smear of mustard or Japanese mayonnaise for sharpness, a few rings of onion, an egg laid in alongside the ham. Each stays within the same toasted, molten frame. The egg addition in particular, which turns it into something closer to a pressed breakfast sandwich, is enough of a distinct experience that it deserves its own article rather than being crowded in here.