For bread crumbs, in blender or food processor coarsely process one roll. In large bowl combine turkey, egg, 1 cup of the crumbs, 1 tablespoon of the mustard, and the salt and pepper. Shape turkey mixture into four patties.
In extra-large nonstick skillet cook turkey patties in hot oil over medium heat for 12 minutes, turning once, or until no longer pink (165 degrees F).
3. For mustard sauce, in small bowl combine mayonnaise and remaining 2 tablespoons mustard. Spread some sauce on remaining four rolls. Layer turkey patty, tomato, avocado, a dollop of sauce, and roll top. Makes 4 servings.