How to cook
Clean and wash the mushrooms, onions, carrot and cut them into small pieces. Put them in a saucepan, full of water and cook for 30 minutes.
Add the rice and cook until it softens completely. Finally, add the tomato juice and cook for a short while.
Shortly before removing the soup from the heat, add as much salt as you like, add the butter and sprinkle with parsley.
Serve the mushroom soup hot, sprinkle it with black pepper and add as much vinegar as you like (optional).