Whisk the vinegar, 1/4 teaspoon of salt, and 1/8 teaspoon of pepper in a large bowl to blend. Gradually whisk in the oil to blend. Add the lettuce, radicchio, beans, and sun-dried tomatoes. Toss to coat. Season the salad, to taste, with more salt and pepper, and serve.
Recipe courtesy of Giada De Laurentiis