2 pounds medium potatoes, like Yukon Gold
1 large thyme sprig or 1/2 teaspoon of dried thyme
1 pound small French beans
4 large eggs
1 tablespoon thinly chopped chives (optional)
2 tablespoons roughly chopped parsley (optional)
2 tablespoons roughly chopped basil (optional)
6 to 8 anchovy fillets for garnish (optional)
Vinaigrette
3 garlic cloves, smashed to a paste with a little salt
1 tablespoon chopped anchovy
1 tablespoon chopped capers
2 teaspoons Dijon mustard
4 tablespoons white wine vinegar
1/3 cup extra virgin olive oil
Salt and pepper
In a small bowl, stir together the garlic paste, anchovy, capers, mustard and vinegar. Slowly whisk in the olive oil. Season to taste with salt and pepper. Whisk again before using.
Add the potatoes, bay leaf and thyme to a large pot of salted boiling water. Simmer briskly until potatoes are firm but easily pierced with a skewer, about 30-40 minutes. Remove and set aside. When the potatoes are cool enough to handle, remove the skins with a paring knife. Carefully slice potatoes 1/4-inch thick, or slightly thicker. Put the slices in a low bowl, season lightly with salt and pepper and add half the vinaigrette. Using your hands, gently coat the potatoes with the vinaigrette, taking care not to break them. Cover and set aside at room temperature.
Trim the beans. Simmer in salted water until firm-tender, 3 to 4 minutes, then cool under running water, pat dry.
Add the eggs to a medium pot of rapidly boiling water and cook for 8 minutes for a somewhat soft-centered yolk or 9 minutes for a firmer yolk. Cool the eggs immediately in ice water, then crack and peel. Cut each egg in half and season lightly with salt and pepper.
Season the beans with salt and pepper, then dress with the remaining vinaigrette. (Reserve 2 tablespoons vinaigrette for the arugula, if using,)
To serve, combine the dressed beans and potatoes, using hands to toss, and pile onto a platter. Sprinkle with herbs and arrange the eggs over the top. Garnish with anchovy fillets, if desired.