A friend just told me this: her Italian New York mother adores an Italian cookie called a Savoiardi. Apparently it has a distinctive "crackly" surface appearance. She baked batch after batch, trying all kinds of tricks, but could not reproduce the surface. Finally she called a local Italian bakery and asked, and they said, "no, we won't tell you that, it's a trade secret." And they hung up on her. Anyone willing to break omerta on this?