Radicchio has an unmistakable snappy bitterness that's a great contrast to the mild sweetness of other lettuces and baby greens. It's a lettuce with backbone. Its distinctive flavor, candy-cane color, and crinkly crispness add spirit to salad. And, though salad is its natural hangout, radicchio has enough character to stand up to grilling, sautéing, or baking.