Sorry - no step-by-step pictures for this one.
I'd written yesterday about the sushi dinner we had to celebrate/reward my son's completion of the guitar book (lessons) he's been working his way through this past year and a half. Among other things, my husband made a variation of eel sauce, or Tsume Sweet Sauce, to serve on broiled tilapia (since we didn't have any eel to cook.)
The recipe Bill came up with is a variation on one in Nobu - The Cookbook. Nobu's recipe calls for 32 sea eels, and unfortunately we lack the funds to justify such a splurge. So Bill created his own recipe. And here it is, pretty much. (He didn't take notes - I'm just going with my understanding of his thought process.)
2 quarts fish stock (or, if you prefer less emphasis on the fish flavor, use a quart of fish stock and a quart of water. But don't use ALL water - you'll lose a lot of the complexity of flavor.)
7 oz white sugar
1/2 cup + 2 T soy sauce
1/4 cup sake
What to do:
Place all the ingredients in a heavy sauce pot (we have a Le Creuset dutch oven that we use - very thick bottom on it - point is, you don't want the sauce to burn).
Bring to a simmer over medium heat, stirring every now and then to check the consistency. You want the sauce to reduce by two thirds, so, if the sauce is about 3" deep at the start, you need to simmer it down to 1". At this point, scrape the sauce out of the pan and into a bowl and let it cool to room temperature. As the sauce cools, it will thicken, which is what you want it to do.
Funny story - well, funny in retrospect. When Bill made this for the first time, following the directions, he ended up burning and ruining the sauce - the sugar basically overcaramelized and burned. The directions in Nobu's book tell you to "Simmer until the liquid is thick enough to dribble in a sticky thread from a spoon." But the problem with that is that if you're simmering at medium heat, the sauce is going to be too hot to thicken the way you want it to. Trust me - once it cools, it WILL thicken. In fact, it will get so thick that when it's been in the bowl in the fridge for a while, you can (or should be able to) hold the bowl upside down and the sauce won't go anywhere. Yes - fun party trick! This here's a multi-purpose website, folks!
Anyway, the lesson to learn is - don't worry about getting the sauce glaze-thick while it's hot. Just reduce it by two thirds and you'll be fine.
What did we do with the glaze?
We made these:
Since, like I said earlier, we weren't about to go and get 32 sea eels, we used tilapia instead. We've also used fresh sardines, which work well.
Bill took a couple nice tilapia filets and cut them on the bias into strips. He marinated them in a little soy sauce for maybe fifteen minutes or so, just to give them a bit of color. Then he put the strips of fish under the broiler until they were just cooked. Then, when they were cool enough to handle, place them on top of your sushi rice, brush some of the glaze over the tops. You'll probably need to warm the glaze briefly if it's been in the fridge at all.
And that's the story of the eel/non-eel sauce we had the other day.