Cover potatoes with salted cold water by 1-inch, then simmer until just tender, 10 to 15 minutes. (Potatoes will continue to cook after draining; do not overcook or they will break apart.) Drain potatoes and rinse under cold water until slightly cooled. Halve lengthwise and while still warm gently toss with 1 tablespoon vinegar. Cool potatoes to room temperature, then season with salt and pepper.
While potatoes cook, in a food processor pulse mixed herbs, shallots, garlic until finely chopped. Add oil, zest and remaining 3 tablespoons vinegar in a food processor until finely chopped.
Toss potatoes with herb dressing.
Adapted from Gourmet Magazine