Pour boiling water over the TVP until just covered (about 1¼ cups / 300 ml).
Let sit for 10 minutes.
Drain well and squeeze out any excess water.
Sauté the onion for 4-5 minutes.
Add the garlic and cook for another 30 seconds.
Stir in the TVP and the TVP seasonings and cook for 2-3 minutes.
Combine the vital wheat gluten, chickpea flour, and nutritional yeast.
Add the cooked TVP mixture.
Mix in the ½ cup (120 ml) water, soy sauce, and mustard.
If the dough feels too dry, add a little more water, 1 tablespoon at a time.
Knead into a dough. Do not knead too long, as this will make the seitan more rubbery.
Let the dough rest for 10–15 minutes.
Divide into 4 equal burgers.
Lightly brown the burgers for 1 minute per side.
Add ½ cup (120 ml) of water to the pan and immediately cover with a lid.
Simmer for 20 minutes.
If the water evaporates too soon, add another splash.
Remove the lid and let any remaining water evaporate.
Fry the burgers for 2-3 minutes per side, until deeply golden.
Let the burgers cool for 10 minutes before serving, or refrigerate overnight and reheat the next day.
