This lettuce is often used in Italian dishes, served grilled, braised or raw in a salad. It has a slightly bitter taste and should be balanced off with either sweet lettuces or a sauce that has some sweetness. To purchase look for one that is firm and without any dark areas. Outer rotten leaves can very often be a warning that the lettuce has been badly handled or seen bad weather. Radicchio lettuce goes bad easily and if the outside is rotten chances are that the center is also.