Rinse the Japanese Short-Grain Rice under cold water until the rinse water runs clear, then drain and place in a rice cooker or pot with the appropriate amount of Water; cook until tender.
While the rice cooks, warm the Rice Vinegar gently in a small saucepan and stir in the Sugar and Fine Salt until dissolved to make the sushi vinegar; do not boil.
When the rice is done, transfer it to a wide bowl, sprinkle the vinegar mixture evenly over the rice, and fold gently with a paddle or spatula to cool and season without smashing the grains; set aside to come to room temperature.
Prepare the Aburaage by pouring boiling water over each piece or blanching briefly to remove excess oil; squeeze gently to drain and, if needed, cut each piece open and flatten into a pouch shape.
Make the simmering broth by combining about 1 cup water with a piece of Kombu in a small pot; warm gently to extract flavor, remove the kombu before it boils, then add enough Dashi Stock (powder or liquid) to taste along with soy sauce, mirin and a bit more sugar to create a balanced sweet-salty braising liquid.
Add the prepared aburaage to the simmering broth and simmer on low for 10–15 minutes until the pouches are glossy and well flavored; remove from the broth and let cool until easy to handle.
Toss a small handful of White Sesame Seeds into the seasoned rice (or sprinkle on top later) and finely chop some Pickled Ginger to mix into a portion of the rice or reserve for garnish.
Gently open each aburaage pouch and spoon in a portion of the seasoned rice, pressing lightly to shape; fold or pinch the opening closed so the rice stays inside.
Arrange the inarizushi on a platter, sprinkle with extra sesame if desired, and serve with the reserved pickled ginger on the side for a bright contrast.
