Ingredients
2 pounds small red and Yukon gold potatoes, halved (quartered if large)
2 tablespoons plus 1 1/2 teaspoons coarse salt
2 tablespoons red wine vinegar
1 tablespoon Dijon mustard
1/3 cup extra-virgin olive oil
1 small red onion, cut into 1/4-inch dice (about 1/3 cup)
5 cornichons, rinsed and sliced into thin rounds (about 1/4 cup)
2 tablespoons capers, rinsed and coarsely chopped
2 tablespoons coarsely chopped fresh flat-leaf parsley
1/4 teaspoon freshly ground pepper
Preparation
Cover potatoes with water in a medium saucepan. Add 2 tablespoons salt. Bring to a boil; reduce heat, and simmer until tender, 7 to 9 minutes. Drain potatoes, reserving 1 tablespoon cooking water. Let potatoes cool slightly.
Make the vinaigrette: Whisk together vinegar, mustard, and reserved cooking water in a small bowl. Gradually add oil, whisking until emulsified. Transfer potatoes to a medium bowl, and drizzle with vinaigrette. Add onion, cornichons, capers, parsley, remaining 1 1/2 teaspoons salt, and the pepper. Using a large spatula, gently stir to combine.
