Peal veggies if you choose. Be sure to scrub them all well. Yes, you don’t really have to scrape or peel if you don’t want to.
Chop all veggies approximately the same size. But don’t worry too much as this gets all cooked through and blended in the end.
Place onion, celery, shallot and carrot in pot and sauté about 2-3 minutes until fragrant. Add garlic and sauté another 30 seconds. (Keep a cup of water nearby for sticking issues and splash a bit in carefully when needed).
Add sage, potatoes, cashews and water in the pot and give a good stir. The water should just cover the veggies.
Cover, bring to a boil, reduce and cook until tender, 15-20 minutes. DO NOT drain.
Add the tahini and the nutritional yeast.
Adjust salt and seasonings. Blend in batches in a blender/Ninja.
If not using a Ninja or Vitamix but using an older version blender let the soup cool off a bit before blending as the steam/heat will not keep the lid tight.