Roasting radicchio is an easy way to impress your friends and family. Radicchio's bitter flavor mellows and sweetens in the oven producing a flavorful, beautiful, uncommon dish. At the Dirty Girl Produce stall people often see the piles of radicchio and say "How pretty! But what do you do with it?" Uncooked radicchio can be good in salads - see Sarah Henkin's recipe -- but roasting is so appropriate when the weather is cool, and you need nothing more than a few heads of radicchio, olive oil, salt and (if you like) balsamic vinegar and Parmesan cheese.
Here's what I do:
Preheat oven to 400F. (I often make this when I have just roasted a chicken and the oven is already hot.)
Take two or three heads of radicchio and quarter them lengthwise so that the stem is still holding the leaves together at the bottom of each quarter. If the heads are especially large I will halve them and then slice the halves into thirds so the wedges are smaller. I do not wash the radicchio first. I simply remove a couple of the outer leaves. If you do wash them make sure to dry them very well otherwise the radicchio will come out of the oven mushy.
Place radicchio in a baking dish and coat each wedge with olive oil. I use a pastry brush so that they're lightly, but completely, covered. Sprinkle with salt.
Place in the oven for 10-20 minutes depending on the size of the radicchio heads. The leaves should wilt and slightly char and the core should soften quite a bit.
Remove from the oven and drizzle with good quality balsamic vinegar. Grated Parmesan and fresh black pepper are also tasty.
Sauteed radicchio is also super easy and good. Slice head into thin strips and saute with olive oil in a medium hot pan until wilted. Season with salt and pepper. Great on brown rice or - even better - polenta.
Grilled radicchio is delicious too. Quarter radicchio and toss with olive oil. Grill for 15 minutes or so until tender and slightly charred, turning every few minutes. Toss with salt, a garlicy vinaigrette, and croutons.