After soaking the tofu with water for 5-10 minutes, drain the water over the sink, Cut it into 6-8 pieces of cubes and transfer to a clean plate, then microwave it for 3 minutes on high settings.
Remove the tofu from the microwave oven and place it in another clean plate once again, then let it dehydrate. Add a coat of cornstarch to fully coat the pieces.
Place a small saucepan on the stove and pour in the Dashi stock, mirin and soy sauce, then turn on the stove to medium heat until the sauce mix gets warm enough. Now turn off the stove and cover the saucepan with a lid.
Pour cooking oil in a nonstick frying pan and fill it at about 1/4 to 1/2 of an inch and set the heat to 171.11 – 176.67 °Celsius. Put in the tofu slowly and deep fry them for about 5 minutes or until they become golden brown in color.
Once done then transfer the tofu to a clean plate lined with paper towels to drain the oil off of the tofu. Garnish the tofu with chopped scallion and grated daikon, then pour some sauce on the top to finish.
Garnish with bonito flakes and Japanese chile flakes, if desired.