I think it's just her adaptation of Taiwanese Mushroom Seasoning. The ingredients are usually just salt and powdered Shitaki mushrooms and was developed as a replacement for MSG (mushrooms are high in glutamic acid so they provide the same umami flavor enhancement that MSG does).
I don't know if mine has any resemblance to hers but I use a powder that I make by whirring up dried shrooms and dried onions in the coffee grinder. Roughly 3 parts Porcini, 1 part morel, 1 part dried onion bits. I keep it in a mason jar and make sure I shake well each time i use it. Great flavor.
Michelle Tam did mention in her 10/31/12 blog post that you should have your friend email the recipe to you if you don't have the app...so anyone with the app want to email it to this person?
I don't have the pleasure of being an iPad owner...if I did, I'd be all over that app!
Only mentioning it since Michelle herself made that statement...
I have the iPad app except I loaned my iPad out till this weekend. If you want to leave me your email addy ill send it to you as long as its one of the free ones, not all the recipes are free with the app many you have to pay extra for