After I made this, I think buying agedashi tofu now is pretty ridiculous because this dish is ridiculously easy to make.
For the tofus, simply fry soft tofu! Just coat the tofu squares with corn flour. I used a mixture of corn flour and rice flour. Dust the squares of soft tofu just before you want to plop them in the hot oil. I realised that when I did the coating early and saw that while I was waiting for the oil to get hot, the tofu disintegrated. It got stuck tot he metal bowl and somehow sitting in the corn flour mixture made them go soft. Luckily for me, I managed to salvage whatever I had.
The sauce is just dashi stock, soy sauce, sugar. Well, the original recipe also calls for sake and mirin. Even omitting the alcohol resulted in a yummy sauce.
And then, add the two together and you get agedashi tofu!