Wash the nameko mushrooms and drain well. Grate the daikon radish and cut mitsuba into 2cm pieces.

In a pot, combine the seasonings (mirin, soy sauce, water), grated daikon, and nameko mushrooms. Heat on low for 3 minutes.

Wrap the firm tofu in paper towels, place in a microwave-safe container, and heat at 600W for 2 minutes. Remove excess moisture and let cool.

Cut the tofu into 4 pieces and coat each piece evenly with cornstarch. Heat salad oil in a frying pan and fry the tofu on medium heat until golden brown.