First, make a broth. The broth is the canvas on which the soup is painted. I made a very simple base using: celery, carrots and a seasoning blend [bay, paprika, garlic powder, dehydrated onion and nutritional yeast.
Don't salt the broth because that reduces flexibility of the finished product. It's best to salt the soup at the end. Otherwise, it can reduce and become too salty.
In a separate pan, boil a medium chopped potato. While that's cooking away, rehydrate a selection of your favourite mushrooms. Now, I always like to use fresh, but finding these unique funghi can be a challenge. So, I've chosen dehydrated: black trumpet, oyster and porcini.
Simply pour boiling water over them and allow them to reconstitute ~20 minutes, or until tender. At this stage, the broth should also be ready.
Remove the mushrooms from the water and set aside. Add the water from the mushrooms to a high speed blender. *Often there's grit that sinks to the bottom when rehydrating mushrooms. Be cautions to prevent adding the grit to the mix.* Then, add into the blender the broth, cooked (drained) potato and most of the mushrooms. I like to select a few mushrooms for garnish and set them aside. This provides both texture and aesthetic enhancement.
Pulverize the mix in the blender until velvety and creamy. Season with salt, to taste, and blend until thoroughly mixed! Garnish with the reserved mushrooms and serve piping hot.