• Gather all the ingredients.
  

To Prepare the Ingredients

• Clean 1 matsutake mushroom with a damp paper towel. Because mushrooms absorb moisture like a sponge, we try not to wash the mushroom. Shave off a thin sliver of the mushroom stem as if you are sharping a pencil with a knife. Cut into thin slices.
  
• Tie a knot in each stem of 4 sprigs mitsuba (Japanese parsley). If you use scallion, finely slice it.
  

To Make the Dashi

• Gently clean 1 piece kombu (dried kelp) with a damp cloth but leave the white powdery substance which contributes to the umami flavor in the dashi. Do not wash the kombu.
  
• In a medium pot, put the kombu in 2 cups water. Heat up slowly on medium-low heat. If you have time, soak for 3 hours ahead of time or preferably overnight. The kombu’s flavor comes out naturally from soaking in water.
  
• When boiling, add 1 cup katsuobushi (dried bonito flakes). Simmer for just 30 seconds and turn off the heat.
  
• Strain the dashi through a fine-mesh sieve set over a bowl. Gently squeeze to release the extra dashi into the bowl.
  

To Make the Soup

• Transfer the dashi back to the saucepan and bring to a boil. Add the seasonings: 1 Tbsp sake, 2 tsp mirin, 2 tsp soy sauce, and ½ tsp Diamond Crystal kosher salt.
  
• Cut 5 oz soft/silken tofu (kinugoshi dofu) into small cubes and add to the soup. Then, add sliced matsutake mushrooms and cook until ingredients are heated through, about 2–3 minutes.
  
• Soak 4 Temari Fu (wheat gluten) in water to hydrate. When the temari fu is soft, squeeze the water out and place it in a serving bowl.
  
• Add the mitsuba to the soup right before serving.
  

To Serve

• Serve the soup into bowls and garnish with yuzu zest on top.