Place the seitan in a large bowl or dish and add in all the marinade ingredients. Mix well with your hands, making sure the seitan is coated very well with the marinade and all the piece are separated and not stuck together so every bit of it can absorb the flavours.
Cover with cling film and leave in the fridge for ten minutes – 24 hours. The longer you can leave it the better.
Just before you’re ready to cook your tacos start getting all your taco toppings ready. There are no hard and fast rules on what you include. We’ve listed what we like to put in, but if you don’t have time to pickled onions or chillies, just substitute some shredded cos lettuce for crunch and some chilli sauce for acidic heat!
Heat 2 tablespoons of oil in a large frying pan. Remove the seitan from the marinade and add to the hot oil, reserving as much of the liquid as you can.
Make sure the seitan isn’t too crowded in the pan and mix gently to coat with hot oil and leave to brown on one side (this should take 5-10 minutes at a medium-high heat) before flipping the seitan over to cook on the reverse side.
Once brown and crisped all over, add the remaining marinade and cook on a medium-high heat to reduce down. When the liquid has almost disappeared, remove the pan from the heat.
Heat 1 tablespoon oil in another pan. Let the oil get very hot then add as many tortillas as you can fit in the pan, without crowding.
Cook the tortillas for a couple of minutes on each side, ideally until they puff up in the middle.
Remove the tortillas from the pan and top each one with a generous tablespoon of seitan, salsa, pickled onions, chillies, sour cream and coriander cress.
Squeeze a lime over all of them just before serving for extra zing and eat with your hand while hot – no cutlery allowed!