Place the whole potatoes into the instant pot, add enough water to cover them, and secure the lid. Set to high pressure for 10-12 minutes until potatoes are tender when pierced with a fork. Release pressure naturally for 5 minutes, then quick-release remaining pressure.
Remove the cooked potatoes carefully with tongs and transfer to a large mixing bowl. Let them cool for a few minutes until they can be handled without burning.
Using a chef's knife, peel the potatoes if desired, then cut them into uniform bite-sized cubes. Add the chopped dill pickles to the bowl with the potatoes.
In a small bowl, whisk together Dijon mustard, mayonnaise (if using), and chopped herbs until combined and slightly thickened. Pour the dressing over the potatoes and pickles.
Toss gently with a silicone spatula until all ingredients are coated evenly. Season with salt and black pepper to taste. Chill in the refrigerator for at least 15 minutes before serving to allow flavors to meld.
Serve the potato salad chilled, garnished with additional fresh herbs if desired. Observe the creamy, chunked potatoes with bright herbs and tangy pickles in a vibrant dish.
