In small bowl, mix ranch dressing and chipotle chiles; set aside.
Heat 10-inch nonstick skillet over medium-high heat. Add corn; cook 5 minutes, stirring frequently, until lightly browned.
Divide lettuce evenly among 4 salad plates. Top evenly with chicken, corn, tomato and onion. Drizzle each salad with 3 tablespoons dressing. Sprinkle with tortilla strips.