Butter Yaki sauce
 

I am trying to trace down a so-called butter yaki sauce which has the ingredients:

Cream, butter, miso, sake

I cannot find all of those anywhere online via searches.

Any ideas on proportions or degree of reduction?

I'd like to dial it in a little before beginning the experimental phase of this research project...

No need for a recipe, since im classically trained in French same process. 1/4 c sake in sauce pan, reduce to a glaze. add cream i cup reduce by 2/3, add 1T miso, don't boil, shut off heat, whisk in 3T butter, s and p to taste

You can add minced shallots or white onions when reducing the sake, only 2tsp

It's basically a french butter sauce w an asian twist. What are you serving it on?

most likely on grilled fish (but I saw some partial iingredient type recipes that were similar and used red miso on steak)

Sounds good will have to try, love Miso. It would be good on Shellfish and even asparagus.

Garnish w micro greens or the green part of a scallion

If it is boring, as butter-cream sauces can be (IMO anyway), try a little bit of heat. In France I suppose one might use Dijon, but here I'd try wasabi.

Good idea, Don't boil the dijon it might break, very salty too, the wasabi is a great idea asian flair and a nice gentle green hue