If fresh chervil isn’t available, substitute an additional ½ tablespoon of minced parsley and an additional ½ teaspoon of minced tarragon. For best flavor, serve the salad warm, but to make ahead, follow the recipe through step 2, cover with plastic wrap, and refrigerate. Before serving, bring the salad to room temperature, then add the shallot and herbs.
2 pounds (about 6 medium or 18 small) red potatoes, scrubbed and cut into ¼-inch-thick slices
2 tablespoons salt
1 medium garlic clove, peeled and threaded on a skewer
1½ tablespoons champagne vinegar or white wine vinegar
2 teaspoons Dijon mustard
¼ cup olive oil
½ teaspoon ground black pepper
1 small shallot, minced (about 2 tablespoons)
1 tablespoon minced fresh chervil leaves
1 tablespoon minced fresh parsley leaves
1 tablespoon minced fresh chives
1 teaspoon minced fresh tarragon leaves
1. Place the potatoes, 6 cups cold water, and the salt in a large saucepan. Bring to a boil over high heat, then reduce the heat to medium. Lower the skewered garlic into the simmering water and blanch, about 45 seconds. Immediately run the garlic under cold tap water to stop the cooking process; remove the garlic from the skewer and set aside. Simmer the potatoes, uncovered, until tender but still firm (a thin-bladed paring knife can be slipped into and out of the center of a potato slice with no resistance), about 5 minutes. Drain the potatoes, reserving ¼ cup cooking water. Arrange the hot potatoes close together in a single layer on a rimmed baking sheet.
2. Press the garlic through a garlic press or mince by hand. Whisk the garlic, reserved potato cooking water, vinegar, mustard, oil, and pepper together in a small bowl until combined. Drizzle the dressing evenly over the warm potato slices; let stand 10 minutes.
3. Meanwhile, toss the shallot and herbs gently together in a small bowl. Transfer the potatoes to a large serving bowl. Add the shallot-herb mixture and mix lightly with a rubber spatula to combine. Serve immediately.