Brown butter over medium heat until golden brown, stirring constantly. Set aside.
Bring water and 1 teaspoon of salt to a boil. Add bay leaves and carrots and cook for 2-3 minutes. If using fresh pumpkin add it now.
Add potatoes to pot with carrots. Cook until fork tender, approximately an additional 12 minutes.
Drain vegetables, reserving water. Discard the bay leaves.
Add all remaining ingredients to blender and process until smooth. Use only 1½ cups water to begin with. Add additional water if needed for desired consistency.
Return soup to saucepan and heat thoroughly before serving.
Garnish as desired.
Notes
Unless a large blender is used the soup will need to be processed in two batches.
Salted or unsalted butter may be used, adjusting salt accordingly.
Canned pumpkin or fresh pumpkin may be used. If fresh is used it should cooked with the other vegetables.
Vanilla extract, paste or vanilla scraped from a vanilla bean may be used.