What about https://en.wikipedia.org/wiki/Mycoprotein (fungal protein)?

I don't know much about it but it's intrigued me for a while. Apparently the only commercial product ("Quorn") is made in a fermentation vat with glucose syrup and Fusarium venenatum spores.

But the nutrition content is interesting: 42% protein by mass yet still has fiber and other nutrients. It's also supposed to be highly satiating.

Unfortunately, Quorn is shipped from the UK and they don't let me buy just one $10 box of it where I live.

As someone in the UK this is kinda strange to read someone wanting to try quorn like I've been wanting to try the impossible burger.

Honestly Quorn is not a great meat replacement for anything other than mince, or maybe foods that are so processed all you can taste are the additives.

Heh. As someone who eats textured soy chunks, I assure you my expectations aren't too lofty.