- 2 lb. small red potatoes (about 12), halved or quartered
- 1 1/2 tsp. kosher salt, plus more for the water
- 4 oz. snap peas, trimmed
- 3 stalks celery, chopped, plus 1/2 cup celery leaves
- 1/2 c. mayonnaise
- 1/2 c. fresh parsley, plus chopped parsley for topping
- 1/4 c. buttermilk
- 1/4 c. chopped fresh chives, plus more for topping
- 2 tbsp. fresh lemon juice (from 1 lemon)
- 2 tbsp. chopped fresh tarragon
- 2 anchovy fillets
- 2 medium shallots, roughly chopped
- 1 small ripe avocado
- Black pepper, to taste
- Put the potatoes in a large pot and add enough water to cover by 1 inch. Season with salt. Bring to a boil over high heat and cook until the potatoes are fork-tender, about 10 minutes. Remove the potatoes with a slotted spoon and place them in a large bowl.
- Add the snap peas to the boiling water and cook until just crisp-tender, about 1 minute. Drain, then thinly slice on an angle. Add to the bowl with the potatoes; add the chopped celery.
- Meanwhile, make the dressing: Combine the mayonnaise, parsley, buttermilk, chives, lemon juice, tarragon, anchovies, shallots, avocado, celery leaves and 1 teaspoon salt in a blender and blend until smooth.
- Once the potatoes have cooled slightly, pour the dressing over the vegetables, season with the remaining 1⁄2 teaspoon salt and a few grinds of pepper and toss well. Cover and refrigerate until chilled, at least 1 hour or overnight. Toss the potato salad again and top with more parsley and chives before serving.