The croque is France's version of grilled cheese, and they definitely don't skimp! Take two slices of regular sandwich bread and spread a handful of grated Gruyère (or Swiss, if you can't find it) on one half. Top with thin-sliced deli ham. Add another generous layer of grated cheese. Top with the other bread slice, and toast in the skillet until the cheese is completely melted and the bread is golden brown on both sides.
Optional: Spread the inside of the top bread slice with bechamel sauce for an authentic, gourmet touch. You can also briefly cook this sandwich under the broiler.
Variation: A croque-madame is made the exact same way but topped with a fried egg for extra oomph.