Soak the seaweed in water for 15 minutes until softened. Cut the tofu into small pieces. Clean the mushrooms with diluted vinegar and salt, then slice thinly. Rinse the noodles with water and drain.

Add 8 1/2 cups water (2 liters) to a pot with 2 tablespoons miso paste. Bring to a boil, then season to taste. Add the dried noodles and cook. If using fresh noodles, skip this step.