There are lots of ways to make a ham and cheese sandwich, but if you ask me, the French way is best. I had my first croque monsieur shortly after moving to Paris 25 years ago, at a bygone café on the rue Royale. I let a French friend order for me, and the waiter brought out the most marvelous thing: a puffy grilled cheese sandwich, dotted with little islands of crisped, golden cheese and covered with a creamy béchamel sauce that encased the toasted bread and jambon de Paris. My friend's version looked just as good, only hers was topped with a barely set fried egg: a croque madame.
Over the years, I've dismissed the misty folklore that says the croque came to be when some workmen left their ham and cheese sandwiches next to a radiator. Regardless, by the 1920s, it was a staple of the cafés along the grand boulevards of Paris. And I've learned that there's no single way to make one. At Le Nemrod, the lively Left Bank café that's my go-to address for really good croques, they serve them not with a classic béchamel, but with a sauce made of whipped, grated Emmenthal, milk, cream, and blond beer. What never changes are the basic ingredients: ham, cheese, and bread. A perfect combination, if ever there was one. —Alexander Lobrano, author of the newly updated Hungry for Paris (Random House, 2010)