Heat oil in a wok over medium heat, and saute mushrooms, onion, and celery or carrot in the oil for 10 minutes.
Add chicken or vegetable stock, rice, and soy sauce. Bring to a boil, and simmer for at least an hour.
Take mushrooms, onion, celery and rice out of the soup. Using a blender or food processor, blend until smooth. Stir back into wok. Season with salt and pepper, and serve hot.
