8 medium leeks, trimmed of tough green parts
Kosher salt, to taste
5 tbsp. red wine vinegar
2 tsp. Dijon mustard
Freshly ground white pepper, to taste
7 tbsp. olive oil
4 sprigs parsley or thyme
1 hard-boiled egg, chopped
1. Starting about 1″ above root end, slice leeks lengthwise, but not all the way through. Open leeks like a book and wash well in cold running water to remove all sand and dirt. Bring a 12″ deep-sided skillet of salted water to a boil, add leeks, and cook over medium heat until soft but not mushy, about 6 minutes. Transfer leeks to a large bowl of ice water to stop them from cooking further. Carefully split leeks completely in half lengthwise, and transfer to a rack, cut side down, to drain thoroughly.
2. Whisk vinegar, mustard, and salt and pepper together in a small bowl. Gradually add oil, whisking constantly, until vinaigrette is smooth and creamy. Adjust seasonings and set aside.
3. Divide leek halves equally among 4 warm salad plates. Drizzle vinaigrette over leeks, and sprinkle with chopped parsley and egg.
Modified from http://www.saveur.com/article/Recipes/Leeks-Vinaigrette