Combine 5 cups water, the butter, the carrots and potatoes in a saucepan. Bring to a boil and cook until the potatoes are tender. Add the pickles and continue to boil.
Meanwhile, whisk together the flour, sour cream and salt in a separate bowl. Add enough water to make a paste, then slowly, to avoid curdling, add the mixture to the soup to thicken. Bring to a boil, then remove from the heat. Add pickle juice, to taste.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.
Recipe courtesy of Ted Wietrzykowski, Polish Village Cafe