Prepare the cashews first for the cashew cream by covering 1/2 cup of cashews in boiling water. Set aside and let soak for 30 minutes.
Heat a large pot over the stove on medium heat. Add the oil.
Finely chop the onion and garlic. Add to the pot to sauté.
Wash and remove the stems of the mushrooms. Slice the mushrooms and add to the pot with the onion and garlic.
Wash and cut the potato into small cubes (leave the skin on). Add to the pot and sauté until golden. Next, add the white wine (if using) and let it all cook together for a few minutes.
Add the miso paste, balsamic vinegar, thyme and salt and pepper. Then add the vegetable broth. Bring to a boil and then let the soup simmer, covered for 15-20 minutes.
While the soup is simmering, prepare the cashew cream. Remove the water covering the cashews and add the cashews to a high-speed blender. Add 1/3 cup + 3 tbsp of water. Blend until thick and smooth. I find it is easier to blend the cashew cream with a cup attachment for my Vitamix so if you have something similar (magic bullet style), I suggest using that. Add an additional 2 tbsp of water to help with the blending process.
Once the soup is done cooking, add the soup to a blender and blend until smooth. Add the soup back to the pot and add in all the cashew cream!
Top the soup with sautéd mushrooms and parsley to pretty it up! Store the soup in a sealed container in the fridge or freeze it!