The "meat" in this recipe is seitan (yeah, pronounce it like Satan, though I swear it's heavenly). Seitan is a wheat meat made from vital wheat gluten flour, and it's a nice, toothsome alternative to oft-too-soft tofu.
You can buy seitan at the grocery store, but I highly recommend making it at home. The internet offers plenty of seitan recipes, and you'll end up making about 10x as much seitan for half the price of buying it at the store.
varies depending on how you cut the seitan
seitan, cut into nugget-size chunks
Adobo seasoning (in Mexican section of supermarket)