Preheat oven to 375F (190C)
Mix together the base seitan ingredients, mushroom powder and chipotle powder in a bowl. Set aside.
Create liquid mixture in a separate bowl. Reserve 1 cup of the vegetable stock for later, then add the other liquid ingredients and whisk well to ensure all is mixed thoroughly. Add the rest of the vegetable stock and thoroughly combine.
To make the seitan dough, create a well in the dry mixture and gradually add a little less than half of the wet mixture. Stir and continue to add very small amounts of liquid until you reach a very elastic dough-like consistency. If your raw dough tears apart easily, this means too much liquid has been added. The raw dough should be very tough to pull apart. Reserve the remaining half of the wet mixture, which will be used later for the braising liquid and glaze.
Sprinkle the counter top with some of the dry seitan mix. Place the dough onto the counter top and liberally sprinkle with a bit more dry mix. In the case of seitan, kneading is done to help shape and create texture in the dough and not to develop gluten. If you have the right ratio of wet to dry, you should be able to stretch the dough, without it tearing too easily.
Braising:
To prepare the seitan for braising, lightly coat a casserole dish with oil or spray oil. Begin to stretch and flatten the dough until it is about an inch thick. Place the seitan into the casserole dish and then flip, to lightly coat it in the oil. Pour most of the remaining liquid into the casserole dish and then flip the seitan, to coat it in the liquid again.
Bake in the preheated oven for 30 minutes, or until the seitan has started to brown. Carefully, flip the seitan and baste with some of the surrounding liquid. Place back into the oven and continue to cook for another hour or so.
Continue to flip and baste the seitan every 15 minutes. As the dish cooks, the sauce will reduce and thicken into a nice glaze. When done, the seitan should be firm to the touch. Remove from the oven and allow to firm up for a few minutes.
Let cool and slice into thin pieces. Serve and enjoy.

Base seitan mix:
2 1/2 cup vital wheat gluten flour
1/3 cup nutritional yeast
2 tablespoon onion granules
1 1/2 tablespoon garlic granules

Liquid mixture:
2 3/4 cup base seitan mix
1/4 cup dried mushroom powder (dried mushrooms ground in a spice grinder)
2 teaspoon chipotle powder
3/4 cup tomato paste
1/3 cup maple syrup
1 1/2 cup marsala wine
2 teaspoon vegan worcestershire sauce
1 teaspoon liquid smoke
2 1/2 tablespoon apple cider vinegar
1/2 cup tamari or soy sauce
3 1/2 cup vegetable stock