A mille-feuille (or tompouce) is a pastry, consisting of layers of puff pastry with pastry cream in-between (see this if you don't know it).
If you buy it in a pastry store, I find that the glazed top is unique for this pastry. Recipes online tell me that it's confectioner sugar and egg whites, but I think it's something else. It's solid, yet soft. You can see your tooth print in it. It's white and sweet. I can't exactly explain how it differs from regular egg white/sugar icing, but in my opinion it does.
Does anybody have a clue what I'm talking about? Do you know what's in it? Or is it just a basic egg white/sugar icing, and is my mind playing tricks on me?