Bonus Tip: Freeze extra servings of this soup for another day.
After the vegetables are done roasting, take them out of the oven. Carefully add them to the soup pot. Add salt and mix well.
You can use an immersion blender or a vented blender. Place the immersion blender into the soup pot and carefully purée the soup until smooth. If using a vented blender, carefully add the soup into the blender container and purée until smooth. This may need to be done in several batches.
Serve warm with some freshly ground black pepper. Top with some pumpkin seeds, if desired. Enjoy!