Well as long as I am eating low-brow food, at least I managed to eat some authentically French low-brow food this time. Turns out the Croque Madame is the Croque Monsieur I was already familiar with, (i.e. toast + melted Gruyère + ham) plus a fried egg on top. Delicieux! The portion size was alarmingly — practically Americanly — large. I couldn't finish it, but it was tasty.