In a pot, sauté the onion, celery, and carrot until they are softened.
Add the diced potatoes and broth, then let it simmer until the potatoes are tender.
Grate the pickles and sauté them in butter until they are heated through.
Incorporate the sautéed pickles and a splash of pickle brine into the soup.
Temper the sour cream (or cashew sour cream) by mixing it with some hot broth, then stir it into the soup.
Mix in a generous amount of fresh dill for flavor.
Serve the soup hot alongside slices of sourdough bread.
