Transfer chicken to a gallon-size zip top bag. Add 1 chopped chipotle pepper, 3 tablespoons chipotle sauce, garlic, lime juice and Adobo; seal bag. Rub to coat chicken in marinade; transfer to refrigerator. Marinate at least 30 minutes, or until ready to grill.

In small bowl, stir together mayonnaise and 1 tablespoon chipotle sauce until well combined; cover and set in refrigerator until ready to use.

Heat grill to medium-high heat. Add chicken to hot, greased grill grates. Grill, flipping once, until chicken is golden brown and cooked through (internal temperature registers 165°F on quick-read thermometer when inserted into thickest part of breast), about 10 minutes. Lightly toast cut sides of rolls on grill.

To assemble each sandwich, spread both cut sides of roll with 1 tablespoon reserved chipotle mayonnaise. Add chicken to bottom of roll. Layer with 2 avocado slices, 2 tomato slices and 1 lettuce leaf. Replace top of roll and serve immediately.