Lightly rinse the 30 grams dried shiitake mushrooms to remove dust or dirt and put them in a bowl along with the 8 grams konbu and the boiling 3 ½ cups water. Let these rehydrate for 30 minutes.
30 grams dried shiitake mushrooms, 8 grams konbu, 3 ½ cups water
Prepare the other vegetables while you wait for the mushrooms to rehydrate.
When the shiitake have rehydrated, squeeze the extra liquid out of them, and reserve the liquid. Remove and discard the stems from the mushrooms and chop up the caps. Discard the konbu.
Add the 1 tablespoon vegetable oil to a heavy-bottomed pot over medium heat and sauté the 140 grams carrots, 70 grams gobo, and 140 grams daikon along with the 1 teaspoon brown sugar until they are fragrant (about 5 minutes).
1 tablespoon vegetable oil, 140 grams carrots, 70 grams gobo, 140 grams daikon, 1 teaspoon brown sugar
Add the ⅓ cup sake and then allow the alcohol to burn off before proceeding.
⅓ cup sake
Add the reserved shiitake dashi broth into the pot, but don't pour in the sediment at the bottom of the bowl, as it may contain some grit.
Add the 140 grams Japanese taro, 2 tablespoons soy sauce, and 1 teaspoon salt, and let the Kenchinjiru simmer until the vegetables are tender and the soup is flavorful (about 20-30 minutes).
140 grams Japanese taro, 2 tablespoons soy sauce, 1 teaspoon salt
Finish the soup by adding the 300 grams firm tofu and 100 grams shelled edamame during the last few minutes of cooking. Adjust the salt to taste and sprinkle with mitsuba, or other garnishes like green onions, sesame seeds, or shichimi togarashi.
300 grams firm tofu, 100 grams shelled edamame, mitsuba