Add the chickpeas, nutritional yeast, garlic powder, onion powder, cumin, ground coriander, oregano, soy sauce, tomato paste, paprika, black pepper, vegetable stock, dijon mustard and liquid smoke to the food processor and process until well mixed.
Transfer to a mixing bowl and add the vital wheat gluten. Stir in briefly and then get in there with your hands, kneading it a few times in your hands until it goes from soft and sticky until it's just starting to get firm.
Flatten it on a work surface and pat it down into the shape of a large steak. Wrap it in foil (not too tight as it needs room to expand) and place into a steamer basket over a pot of boiling water to steam for 20 minutes.
While the seitan is steaming, make up your hummus and vegan tzatziki.
After steaming, remove from the foil (be careful not to burn yourself) and then cut it into strips and place into a frying pan.
Mix up the soy sauce, paprika, maple syrup, tomato paste, olive oil and liquid smoke for your marinade and pour it over the seitan strips.
Fry the seitan strips in the marinade sauce, turning over regularly, until all the pieces are nicely charred and crispy on the outside.
Spread hummus onto a pita bread or wrap. Add shredded lettuce and sliced cucumber and tomato, top with seitan strips and finish with a dollop of vegan tzatziki.
Repeat for the rest of the shawarmas and serve.