1. Wrap the tofu with 2 layers of paper towels and place on a microwave safe plate. Microwave for about 2~3min at 600w. Let it cool to room temperature. Set aside.
2. In a small cooking pan, add the sauce ingredients and bring it to a boil. Set aside.
3. Cut the tofu into 8 to 10 pieces and coat in the katakuriko/potato starch.
4. Deep fry the tofu until all sides are light brown and crispy. Transfer it to a plate lined with paper towels to drain excess oil.
5. Serving : place the tofu in a serving bowl and gently pour the hot sauce over the tofu. Garnish with green onion. Alternatively you can use grated daikon, katsuobushi, or wasabi. They all make for very nice topping.