Instructions

  1. Heat salted water in a large saucepan until boiling; cook the beans until tender, about 7 minutes. Drain beans; set aside to cool.
  2. Whisk together the garlic, vinegar, mustard, salt and pepper to taste in a small bowl; slowly whisk in the olive oil, adding in a steady stream, until smooth.
  3. Combine the reserved beans, green onions, mushrooms and parsley in a large bowl. Pour dressing over vegetables; toss lightly.
  4. Chill 30 minutes before serving.