Preheat your grill for medium heat. Clean and oil the grill grate.
Combine the eg with the tortillas, pepper, chili powder, salt, pepper and chicken. Mix well to combine. Using your hands, shape the chicken mixture into 4 large patties about 3/4" thick.
Grill the chicken burgers for 14 to 18 minutes, flipping once halfway through cook time, or until 165 degrees F and cooked through. Allow to rest in foil for 5 minutes before serving.
Meanwhile, prepare the Texas Toast according to package.
Serve the burgers open faced over the Texas toast with a healthy slathering of guac and some additional crushed tortillas, fresh salsa, and pickled red onion.