Favorite-flavors salad

For Walnuts:
1 cup walnut pieces
For Potato:
1 baking potato (about 1/2 pound), peeled and cut into 3/4-inch pieces
For Dressing:
1/2 pound Roquefort cheese or other blue cheese, crumbled
1/4 cup wine vinegar
3/4 teaspoon salt
1/4 teaspoon fresh-ground black pepper
1/2 cup mild oil, such as canola
For Salad:
1 head romaine lettuce (about 1-1/4 pounds), cut crosswise into 1/2-inch strips (about 3 quarts)
2 bunches watercress (about 10 ounces in all), tough stems removed, leaves chopped (about 1 quart)
1 cup drained cocktail onions
1 avocado, preferably Hass, cut into 1/2-inch dice
1 pear, peeled, cored, and sliced

1. For walnuts: In a small frying pan, toast the nuts over moderately low heat, stirring frequently, until golden brown, about 5 minutes. Or toast them in a 350 degrees F oven for 5 to 10 minutes.
2. For potato: Put the potato in a medium pot of salted water. Bring to a boil and simmer until tender, about 10 minutes. Drain and set aside.
3. For dressing: Meanwhile, in a large glass or stainless-steel bowl, combine one third of the blue cheese with the vinegar, salt, and pepper. Mix thoroughly and then gradually whisk in the oil. Reserve 2 tablespoons of the dressing.
4. For salad: Add the romaine to the rest of the dressing and toss. Transfer to a platter or salad bowl.Toss the watercress with the reserved dressing. Arrange the remaining blue cheese, the watercress, walnuts, potato, onions, avocado, and pear slices on top of the lettuce.