Wash the kale thoroughly. Separate the leaves and set aside. Blend the leaves and strain through a sieve. Slice the stems thinly on a diagonal, and chop the mushrooms.

Pour water into a pot and bring to a boil. Add the mushrooms, then the sliced stems, and cook until boiling. Season to taste. Next, add the kale leaves and stir well.

Finally, add the silken tofu. Once the soup comes to a rolling boil, turn off the heat. Ladle into a bowl and sprinkle with black pepper.