I purchased a very nice filet from our fishmonger, and would prefer to honor its price.
It’s about 1.5" thick at its thickest part. I thought about blasting it in the air-fryer with a light coating of garlic black bean sauce, but I really want to let the fish shine.
Thank you in advance 
You can treat it like black cod:
As Amanadarama insinuates, a misoyaki marinate a la Nobu’s miso black cod would do it justice. Or can I suggest to steam it chinese style, then cover it with minced ginger, cilantro, green onions, and drizzle it with shoyu and a bit of scalding hot oil. This is how we steam whole fish in Hawaii, and is my favorite preparation for halibut that I bring home from Alaska.
I would have to say . Grilled with lemon , olive oil and salt . Or papillote .
Damn, and I just tossed the itty bit of sake our HK friend gave us before we our Philly sojourn 
I have all the other ingredients, save for the wasabi powder.
ETA: YAYYY! I had not tossed the sake. The purge queen musta missed this one 
And the wasabi oil seems to be for serving, which I may just forgo, but I have everything for the marinade 
Yeah, you can skip the wasabi oil. In the Blue Ginger cookbook, he garnishes the dish with both the wasabi oil (basically, wasabi powder mixed into neutral oil) and a soy syrup (reduced soy sauce, sugar mostly), but neither are critical.
If you didn’t have the sake, a dry white wine or dry sherry would be fine too! The miso is the main thing, the rest just carries it.
I’ll def cut down on the sugar in general — I have to halve the recipe anyway since the filet is only about 2/3 of a pound.
With the mirin, for a half recipe you really only need about a tablespoon of sugar (and I double the ginger and usually also grate in a clove or two of garlic).
Thanks for the pointers! Extra ginger & garlic is always a good thing in my book 
