This is a shortcut on a recipe from the cook-and-educational-book, Bitters, by Jennifer McLagan. The imagery is her's as well. It's so simple and one of my most favorites: so, in a nutshell:
Cut two heads of radicchio into quarters and drizzle with olive oil, turning slightly to coat all of the pieces. Season with salt and pepper. Set a cast iron pan over medium heat, and, when hot, add the radicchio and cook, turning often, until it is soft, brown in color and lightly charred (about 12 minutes). Cut creamy cow's milk cheese into pieces. Transfer the radicchio to your serving dish and top with the cheese pieces and sprinkle with balsamic vinegar. The heat of the radicchio will melt the cheese.
So, it's simply radicchio, olive oil, salt and pepper, your favorite cheese (a creamy one that melts well), and balsamic vinegar. (I've used cream fresh too—with great success.) Enjoy!