Green Goddess Potato Salad - cooking recipe

Ingredients

3/4 lb green beans
3 lbs cooked small boiling potatoes, cooled and quartered
1 cup mayonnaise
3 tablespoons tarragon vinegar or 3 tablespoons white wine vinegar
3 scallions, chopped
3 flat anchovy fillets, chopped or 2 teaspoons anchovy paste
1/4 cup chopped fresh flat-leaf parsley
2 teaspoons chopped fresh tarragon
1 teaspoon salt
1/2 teaspoon black pepper

Preparation

Cook beans in a 3-quart saucepan of boiling salted water, uncovered, until tender crisp, 3-5 minutes.
Drain in a sieve, then plunge the sieve into a large bowl of ice water to stop the cooking.
Drain again, pat beans dry and then cut into 1/4 inch pieces and put in a large bowl with the potatoes.
Pulse mayonnaise, vinegar, scallions, anchovies, parsley, tarragon, salt and pepper in a food processor, or blender, until dressing is pale green and herbs are finely chopped.
Stir into potato mixture.