The first step is to peel the vegetables. Peel the carrots, cabbage, and onions. Take the outer part of the vegetables and wash them. In a vessel, add about 2 liters of water and add the vegetable peels. Let it boil for about 20-30 minutes and set aside.
In a wide kadai, add oil. Then add chopped garlic, ginger and coriander stems. Sauté for about 2-3 minutes. And then add in the vegetable stock. Let it come to a boil and then add sliced onions, chopped carrots, beans, cabbage, capsicum and mushrooms. Let it cook for about 10 minutes and then add in the soy sauce, vinegar, salt and sugar. Let it cook for another 10 minutes.
To this, add 1/2 cup of cornflour slurry and mix. After the soup thickens up, add crushed green chillies, spring onions and coriander leaves.
You can either serve it with momos or serve it as it is as this tastes really amazing as well.