Hydrate the dried hijiki in a decent amount of water, and drain it well. Mince the onion. Roughly mince the carrot and shiitake mushrooms.
Put the ground pork, onion, salt, egg, and panko into a bowl and knead well until it's sticky. Then add the carrot, shiitake mushrooms, edamame, and hijiki. Thoroughly mix everything together.
Cut the aburaage for inari sushi into half (not diagonally). Open up into pockets and stuff the Step 2 meat mixture gently.
Using a large frying pan or a pot, align the aburaage from Step 3 with the open end facing up. Pour in the dashi stock, soy sauce, sugar, and mirin and turn the heat on. When it comes to a boil, turn the heat to medium. Cover the pan and simmer. Pour the sauce over the aburaage occasionally (for 2-3 times) and simmer for 7-8 minutes.
Transfer the simmered inari onto a serving dish. Simmer to reduce any leftover sauce. Add the katakuriko dissolved in water to thicken the sauce. Pour it over the simmer inari to finish.
I've also packed them in bento.
Story Behind this Recipe
This is a variation of meat-stuffed peppers.
Avoid packing the inari too much since the ground meat filling will expand to a certain extent.