Grill or cook the chicken in a saute pan until cooked. Cube the chicken or shred and place in a bowl and mix with the bbq sauce and one chipotle pepper that has been diced fine. Combine the chicken mixture together and keep warm until ready to serve. In a microwave safe bowl, microwave the frozen corn until hot. Chop the lettuce, cilantro and dice the tomatoes. In a separate bowl, combine the ranch dressing, lime juice and other chipotle peppers and mix until smooth. To assemble the tacos, place a good portion of the shredded chicken into the bottom of a hard shell taco. Top with the corn, tomatoes, cilantro, lettuce, and cheese. Drizzle the top of the tacos with some of the chipotle dressing and serve warm.