WELL! I've enjoyed this stuff many times here in the US, originally as canned, now also refrigerated in different forms. I was surprised at the end, since I've always seen this as Vegetarian stuff. I bet it's good cooked with pork belly! I've never had a good idea of how it was made industrially. You can make some gluten yourself and cook it, but it's a lot of work! Also if you use ordinary flour you don't get much gluten, ordinary flour is something like five or ten per cent protein. My first thought was that this factory must be generating a mountain of wheat starch!
Tofu and Seitan are only meat ‘replacements’ in the west. In the East, they are cooked much like a vegetable - could be on its own or could be with meat.
You can just kneat a dough ( water and flour) for 20 minutes and then rinse it with water till you find the gluten structure, it looks like a web. Itßs not that diffucult.
