Dough: In a large bowl stir together all dough ingredients until a ball forms. Transfer to a clean surface and knead for about 5 minutes, or until dough is elastic and cohesive (it will still be lumpy, that's okay!) Form into a log shape. Let dough rest for 5 minutes while you prepare the broth.
Broth: Add all broth ingredients to a large pot and bring to a simmer. Gently lower the seitan dough log into the broth, ensuring the dough is covered by the broth (if not, transfer to a smaller pot). Partially cover and simmer for 1 hour.
Serve: Remove from pot and let cool enough to touch. Slice into slabs, crumble into nuggets, or use however you need it (depends on your recipe and desired use!)