Mix the miso paste in a little hot water until dissolved. Set aside.
Sauté the garlic in the oil in a pan over a medium heat for about 2 minutes or until soft.
Add the mushrooms, carrots, pak choi, spring onions, and soy sauce to the pan. Cook for about 5 minutes or until soft.
Add the water and bring to the boil.
If you are having noodles, add them now and cook for 2 minutes. Add the spinach and tofu at this point too.
Serve hot.
