Radicchio is the darling of high end restaurants and haute cuisine. It is a slightly bitter green closely related to escarole. It is often braised, sometimes grilled, or used as a platform for hors d’oeuvres, as well as added to salads. Here’s a cooked recipe with some beautiful back story. Wow Italians really are obsessed with this stuff. Check out this link, for some above and beyond minutia and details about radicchio and a list of about 20+ recipe links.