Croque monsieur, a popular snack, appeared on French menus in the early 20th century and, according to Larousse Gastronomique, is "a hot sandwich, made of two slices of buttered bread with crusts removed, filled with thin slices of Gruyere cheese and a slice of lean ham", that is "lightly browned on both sides either in butter in a frying pan or under the grill".
It adds that it may also be topped with béchamel sauce and cooked au gratin. The Oxford Companion to Food agrees with this definition in terms of ingredients and cooking methods but notes that it should be cooked until crisp, suggests thick slices of cheese and adds that it is sometimes dipped in egg and breadcrumbed before frying.
French chef Daniel Boulud calls it more simply the "ultimate ham and cheese sandwich".
What is not known is how it got its name, which generally translates to "crunch mister" or "munch mister", or how it came into existence.
In Hong Kong, this French take on a toasted cheese and ham sandwich is a crowd pleaser at both The Langham's Main St Deli and The Lobby at The Peninsula Hong Kong. But which does it better?
The Lobby has a refined, classical ambience befitting such a grand hotel. It has spaciously placed tables, comfortable seating and warm lighting, with tones of blue and brown offset by the tall white columns and gold detailing on the ornate ceiling. The sounds of The Lobby Strings wafting from the mezzanine balcony add to the elegance. The service is faultless. The à la carte menu describes the croque monsieur as "served in Paris in 1910 - white bread filled with shavings of bone ham and Gruyere toasted in butter until golden brown". The 1910 reference is a nod to those, including Larousse Gastronomique, that suggest it was first served that year in a Parisian cafe.