Salad of Bitter Greens and Walnuts Recipe

1/4 cup chopped walnuts
1/4 cup defatted reduced-sodium chicken broth
2 tablespoons tarragon vinegar or white-wine vinegar
2 tablespoons walnut oil or extra-virgin olive oil
2 tablespoons finely chopped shallots
2 teaspoons Dijon mustard
Salt and freshly ground black pepper to taste
16 cups washed, dried and torn mixed greens, such as escarole, chicory and/or radicchio

In a small dry skillet over low heat, stir walnuts until lightly toasted, about 3 minutes. Transfer to a plate to cool.
In a large salad bowl, whisk together chicken broth, vinegar, oil, shallots, mustard, salt and pepper. Add greens and toss thoroughly. Sprinkle with the walnuts and additional black pepper to taste.