The answer is yes! Frozen potatoes can absolutely be used in soup. In fact, they can be a great addition to any soup recipe. There are a few things to keep in mind when using frozen potatoes in soup. First, make sure to thaw the potatoes before adding them to the soup. This will help them cook evenly and prevent them from clumping together. Second, cut the potatoes into small pieces before adding them to the soup. This will help them cook quicker and more evenly. And lastly, don't forget to season the soup well! Frozen potatoes can sometimes be bland, so make sure to add plenty of salt, pepper, and other spices to taste.