I've heard of a vegetarian / vegan meat substitute called seitan. What is it, and can I make it at home? Do I just prepare it in the same way I might cook chicken or beef?
Seitan is a meat substitute made from wheat. It has a meaty, almost beef-like texture and is very high in protein at 75g of protein per 100g of seitan. It is also known as wheat gluten, vital wheat gluten, and mock duck.
You can also buy pre-made seitan from some grocery and health food stores.
Seitan is a substitute mainly made of wheat gluten (so be sure to not have any allergy in this area).
I mostly buy it in dried form and then water it (see the product you choose for more details). After the recommended time, I take it out of the water and squeeze the water out of it. Then I roast it gently and add lots of spices (the taste of Seitan itself is rather neutral). But be aware that it's a very short process of "cooking" (don't put too much heat on it).
Readymade seitan can be bought in various forms - eg as a piece in health food stores, or as canned "mock duck" or "gluten puffs" (very different products!) at an asian grocery, or as part of a semi-convenience products. These should be treated similar to par-cooked meats, can be refined by frying/roasting/sauteeing/marinating...
The same applies to homemade seitan that has been cooked. There are various ways of doing so - eg boiling, steaming, poaching-then-boiling, baking, deep frying. Temperature regimen and whether it is cooked constrained or not, and whether other protein flours are mixed in, affect the result too. Choices of methods here can lead to a vast array of different textural results - as does the kneading method to a degree.
If it is homemade from flour, from scratch (as opposed to vital wheat gluten powder), there are less possibilities of adding in seasonings or textural modifiers (they would get washed out), but there are more choices in the base flour used (spelt can be used though it is more difficult).
The raw dough can be portioned and cooked directly in stew-like (not: braised!) dishes, but this will take very long, can be complicated by the effects of acids in the sauce, and needs good temperature management (boil it before it has set and you'll be left with a very brain-y result. That's why you can't braise it from raw.).