Cut the atsuage as thick as you would cut sashimi (about .5 cm). Combine the soy sauce and mirin and marinate the atsuage in it for at least 10 minutes.
Lightly brown both sides of the atsuage using a or an oven.
Add the marinade of soy sauce and mirin to a small saucepot and heat. Bring to a boil while stirring to thicken it, but be careful not to burn it.
Put the cooked atsuage in the pot with the sauce and mix well. Place in a bowl on top of plenty of rice and top with ground sansho pepper.
Story Behind this Recipe
Today was the day of the ox (thought in Japan to be the hottest day of the year and a traditional day to eat eel). Since I'm a vegetarian, I came up with this vegetarian version of the eel rice bowl.
The thickness of the sauce comes from the mirin, however, if too much of the moisture evaporates off it'll burn in a hurry, so stop the heat before it gets to that point! If you have any eel sauce you can use that or even mix it in for a blended flavor. If you top with lots of sansho pepper you get a taste pretty close to the real deal. Goes pretty well with shredded seaweed and mitsuba.