(Substitute salt for the soy sauce and bonito dashi)
Toast both sides of the aburaage in an oven or the like, and chop into strips.
Pour the soy milk into the pot, heat over low heat, and season with the bonito dashi and usukuchi soy sauce.
Add the vinegar right before the pot comes to a boil, and thoroughly mix. The soy milk will instantly curdle and become lumpy.
Transfer to a bowl, add the aburaage, top with minced green onions, and serve.
For the salty version: Substitute 1/2 teaspoon salt for the soy sauce and bonito dashi. I recommend this version for full enjoyment of the soy milk flavor.
For the salty version, try topping it with zha cai, or strips of whole grilled squid It's also delicious topped with lightly browned dried shrimp.
Story Behind this Recipe
I was craving the xian dou jiang that I had in Taiwan, so I searched for the recipe on the internet. The recipe uses a lot more ingredients, but I adjusted their amount and the seasonings to a simpler recipe that also suits the Japanese palate. Traditionally, xian dou jiang is served with fried bread to soak up the soup, but I used aburaage (thinly sliced fried tofu) instead.
Be sure not to boil the soup Adjust the taste with the vinegar and boil to your desired consistency. It's also tasty drizzled with ra-yu (spicy sesame oil) Season lightly so that you can enjoy the subtle flavors of the ingredients.