1. Preheat oven to 350 degrees F. Bake pumpkin cut side down until very tender (45 minutes to 1 hour). Scrape pumpkin from the peel and puree in a blender, with any juices, in batches. Put pureed pumpkin into your soup pot.
2. Blend cashews in blender until smooth and add to the pumpkin puree. Rinse the blender with a little water and add to the pot. Add a little more water if it's too thick.
3. Add ginger and salt, to taste and heat gently for a few minutes to blend the flavors.
For an even easier variation, use frozen, cooked squash.'