Place sliced potatoes in a large pot.  Cover with cold water by 1 inch. Add two teaspoons of salt and bring to a boil over medium-high heat.  Continue to cook for 5-9 minutes or until the potato slices are just tender. Keep a close eye on the potatoes as they cook and check them frequently for doneness.  You want them to be just tender. If you overcook them they will start to fall apart and not be as beautiful in your salad.

Carefully remove the potatoes from the boiling water with a slotted spoon and transfer them to a strainer to drain.  Save ¼ cup of the cooking water. Lay the potato slices in an even layer on a rimmed baking sheet.

Whisk olive oil, vinegar, mustard, shallot and reserved potato water together in a medium bowl.  Drizzle mixture over the warm potatoes and let sit for 10 minutes.

Add pickled beets, capers and herbs.  Stir gently with a rubber spatula, taking care not to break the potato slices.  Season to taste with salt and pepper. Transfer to a platter and serve.