The only time I've had these was in a restaurant on the Champs d'Elysees in Paris. There were 2 cookies served with white chocolate ice cream with a white chocolate syrup. It was pretty tasty, but the cookies are kind of bland.
My friend claims these are as easy to make as "falling off a log". My first, last, and all of my attempts flopped. Phooey on these puffy things. They're not much to get a tooth around anyhow!