Heat 1 tablespoon of oil in a skillet over medium heat. Add peppers and onion. Heat until they start to soften, about 5 minutes. Add mushrooms and cook for another 2 minutes. Set aside.
Clean pan and add second tablespoon of oil. Add seitan, oregano, and paprika. Cook, stirring frequently, until the seitan browns on both sides, about five minutes.
While seitan is cooking, add provolone slices and water to a saucepan and cook over low heat, stirring continuously, until it becomes saucy.
Place quinoa in a bowl and top with seitan and vegetables. Spoon cheese sauce on top and serve immediately.