To toast walnuts: Preheat oven to 350° F. Spread nuts in a pie pan. Bake 10 to 12 minutes, or until fragrant and just beginning to take on color.
To make dressing: In a nonreactive mixing bowl, whisk together all ingredients except blue cheese. Stir in blue cheese. Refrigerate at least 2 hours and stir well before using.
To make salad: Cut endive diagonally into slices about 3/4-inch thick. In a mixing bowl, place endive, frisee, pear slices and dressing. Toss gently but thoroughly. Arrange salad on 6 plates and garnish with blue cheese squares, walnuts and shrimp.
Makes: 6