Mix together the chili powder, cumin and smoked paprika. Season the chicken with salt, pepper, and half of the spices.
1 teaspoon chili powder, 1/2 teaspoon ground cumin, 1/2 teaspoon smoked paprika, 1 pound boneless, skinless chicken, salt, pepper
Heat the olive oil in a medium skillet over medium heat and add the chicken. Cook for about 5 minutes, or until no longer pink in the center.
Once the chicken is cooked through, add the corn, black beans, and remaining 1/2 teaspoon of the chili powder to the skillet. Stir and cook until heated through, about 2 minutes.
1 cup corn, 1 cup black beans
When you are ready to assemble the pitas, cut the avocado into small cubes, if using.
Place one slice of cheese into each pita and divide the chicken mixture (warm or cooled) among the pockets.
4 slices pepper jack cheese, 4 pitas
Top evenly with the avocado and/or fresh lime, if desired.