Prepare the Tofu: Wrap a block of tofu with paper towels and press it to remove excess water for 5 minutes. Afterward, discard the damp paper towels and cut the tofu into 6 equal pieces.
Prepare the Dashi Soup: In a saucepan, combine dashi powder, mirin, soy sauce, and water. Bring the soup to a gentle simmer over medium heat, then remove it from heat.
Prepare the Toppings: Grate fresh ginger and finely chop scallions, setting them aside for later.
Coat tofu: Cover each piece with rice flour, ensuring an even coating. Shake off any excess flour.
Deep fry the tofu: Heat vegetable oil in a frying pan to 320°F (160°C). Carefully place the tofu pieces into the hot oil and let them fry until they turn crispy. Flip them over to make sure both sides get that nice crispiness. Once they're done, transfer the tofu to a wire rack to let any excess oil drain off.
Serve: Arrange the deep-fried tofu in a serving bowl, topping them with chopped scallion and grated ginger. Pour the hot dashi soup over the tofu.
Notes
Storage: Store any leftover agedashi tofu and the soup in an airtight container in the fridge and consume within 2 days. When you're ready to eat, heat it up in the microwave.
You don't need to press the tofu completely. Retaining some moisture is critical to achieving and preserving a fluffy texture in the final dish.
If you find the tofu coating coming off too easily, mix in some potato starch with the rice flour. This not only adds thickness to the batter but also enhances its crispiness.
Agedashi tofu is best enjoyed fresh and hot. Serve it immediately after pouring the dashi soup over the fried tofu to maintain the crispy texture.