Prep your rolls and warm in the oven to toast. Tip: brush inside and/or outside of bread with olive oil if you'd like.
Prep your veggies
Add oil to skillet and heat over high heat.
Add peppers, onions and optional chilies. Cook until the edges begin to blacken and the onions begin to caramelise. Add in the spices, pepper and salt during cooking process.
When veggies are just about done, add in the cheese and watch it melt over top the veggies. Transfer this veggie / cheese mixture carefully to a sheet of foil or plate.
While pan is still hot, add another small splash of oil and add the seitan strips. Saute until the edges blacken. If your seitan is already seasoned (As mine was) you can just add in some extra spices to taste if desired. Pepper, spicy cayenne, nutritional yeast - whatever you'd like.
Add the veggies + cheese back to the hot skillet and toss with the cooked seitan. Remove from heat.
Add the filling to the rolls. Garnish with the fresh cilantro, tomato and green chilies. Pepper too. Serve hot!