I have two bottles labeled "mushroom soy" in my kitchen, but they are not the same. The Chinese mushroom soy is very dark and flavored with molasses. The Thai mushroom-flavored soy is just that. I bought it on a whim, but have not yet encountered a recipe calling for it.
As not uncommonly happens in my kitchen, a rare bird forced the issue. To make a long story short, an extreme rarity showed up in eastern Pennsylvania and I wound up chasing it with The Lurker and The Blonde Bandit. Since we left mid-morning, I was able to throw together the most random of stir-fries before driving over to The Blonde Bandit's for a rendezvous.
I used abura-age as the protein component of the dish since (as usual), there wasn't any meat thawed. I opened up the bottle of mushroom-flavored soy sauce and sampled it. As advertised, it was a mushroom-flavored soy sauce, and very tasty, too. I used it as the base for a random stir-fry. I mixed some of it up with Shao Xing rice wine and sesame oil, and stir-fried the abura-age in the sauce. As the sauce bubbled up, I added some Chinese mushroom soy to give the sauce some depth, then added more mushroom-flavored soy and rice wine. It was a matter of watching the sauce's consistency in the pan, then adding more liquid (or not) as seemed appropriate. I poured it over leftover rice from Friday night and it all worked out well. Better than the chase, in fact, since we didn't get the target bird.
After our unsuccessful chase, I went to The Cruise Director's and The Fireman's for a Super Bowl get-together. The Cruise Director provided some excellent beef stew, The Deacon brought cookies and a very decadent cake for The Fireman's and The Frog Collector's birthdays. Unfortunately, I flaked out early because of the long day, but The Cruise Director sent me home with a CARE package of stew which made a very good lunch the following day.