Wrap 1 block tofu with paper towel for about 20 minutes. Cut tofu into 8 pieces and roll it in potato starch. Fry tofu at medium heat until golden brown. Put fried tofu in a serving bowl or platter and pour the dashi mixture on the tofu and place the grated daikon on top.
Dashi mixture (sauce): In a pot, add water, dashi, then add mirin and shoyu and bring to a boil and turn off heat.