Cook the seasoning in a large saucepan over medium heat 2 minutes or until toasted, stirring frequently. Combine fajita seasoning, corn, 1 tablespoon juice, and cilantro in a medium serving bowl.
Combine onion, garlic, beans, and bell pepper in a medium serving bowl. Combine avocado and 2 teaspoons juice in a small serving bowl, tossing gently to coat. Combine dressing and chipotle in a small serving bowl.
Place lettuce in a large serving bowl. Place chicken in a medium serving bowl. Place cheese, chips, mango, green onions, and radishes in individual serving bowls. Arrange the bowls, buffet-style, beginning with lettuce and ending with dressing. For each serving: 1 1/2 cups lettuce, 3/4 cup bean mixture, 1/4 cup corn mixture, about 1/3 cup chicken, 3 tablespoons chips, 3 tablespoons cheese, 2 tablespoons mango, 2 tablespoons onions, 1 tablespoon radishes, 1 tablespoon avocado, and 1 1/2 tablespoons dressing.