In a small saucepot over medium high heat, stir together the Kabayaki Sauce ingredients. When the sauce begins to bubble, immediately turn the heat to low and let it simmer for 4 to 5 minutes, until thick enough to coat the back of a spoon. Be careful, as the sauce can easily thicken too much, and you'll end up with caramel! If it becomes too thick, whisk in a tablespoon of water at a time.
Set a large frying pan over high heat. When the pan is very hot, add the oil and swirl to coat pan. Lay the fish fillets in the pan, not touching each other. Fry for 2 minutes until the bottoms are browned. Brush the Kabayaki Sauce glaze on the fillets. Flip the fish over and brush the top of the other side. Fry for another minute or two, until the fish flakes easily and is cooled through.
Serve the fish over rice and pour additional Kabayaki Sauce over the fish. Top with seaweed shreds and green onions.
serve this with lightly sauteed sugar snap peas and rice.