Her process includes marinating the meat in soy sauce and rice vinegar. So last night I dutifully cut up my beef, mixed equal parts soy sauce and rice vinegar in a bowl, covered it, and stuck it in the fridge. And then between housework and a sudden desire to go to the grocery store, I didn't actually cook it last night.
So tonight I drained my marinade, made my stir-fry, cooked some rice, sat down to eat...
IDK if it was the proportions, the sheer volume of marinade (I actualfax covered the meat in liquid), or the fact that I left it marinating for ~24 hours, but congratulations, self! I have just invented SOUR Pepper Steak with Onion. Which would have been great if I liked sour.
(The bell peppers turned out fine though. And the rice. I have never disastrously fucked up a pot of rice.)