Cannellini-Bean Niçoise Salad

Make the dressing: In a small bowl, whisk together lemon juice, mustard, shallot, oil, parsley, basil, and 1/2 teaspoon salt; season with pepper.

Prepare the salad: Place potatoes in a medium saucepan and add enough cool water to cover by 1 inch. Bring to a boil; reduce to a simmer. Cook until tender when pierced with the tip of a sharp knife, about 15 minutes. Drain and set aside to cool.

Bring a pot of water to a boil and prepare an ice-water bath. Blanch haricots verts until crisp-tender and color brightens, 45 to 60 seconds. With a slotted spoon, immediately transfer beans to ice-water bath to stop the cooking; once cool, drain and pat dry with paper towels.