There is a new restaurant in Nihonbashi, just between Coredo (the Merrill Lynch building) and Takashimaya on the block between Chuo Dori and Showa Dori.
Went for lunch and had the "hako meshi". Served in a similar style to an unagi lunch. You could choose if you wanted the anago grilled or simmered. I asked the waitress what the recommendation of the shop was and she said the grilled "yakiage". Our lunch was 1600 yen I believe.
Very tender anago, grilled and served with the kabayaki teriyaki sauce. It literally melted in your mouth. The grilled version was a bit "roasty and toasty" as promised.
It came with bowl of dark miso with some aosa, a delicate seaweed, (I think I have the name right) and some pickles.
For an extra 200 yen you could get a tea pot with a savory broth to make ochazuke with part of your unagi and rice. Definitely recommend doing that.
The shop is a former sakaya (sake store). They have maintained the inside of the shop as it was originally. Dark wood and high ceilings with everything exposed.
The staff were very nice. And, it is open 7 days a week! Highly recommended.