• Cut a small corner from the chicken packaging and drain off any excess liquid. Transfer to a plate; pat dry with a paper towel.
• In a medium bowl, season the chicken generously with salt and pepper and toss with 2 tablespoons chipotle mayo. Set aside the remaining mayo for serving.

In a large frying pan over medium-high heat, warm 2 to 3 teaspoons oil until hot but not smoking. Add the chicken and cook, stirring occasionally, until browned and cooked through, 6 to 8 minutes. Transfer to a plate.
While the chicken cooks, start the mango-avocado salsa.

• Juice the lime.
• Peel and finely chop enough red onion to measure ½ cup.
• Trim off the top and bottom of the mango; cut away the peel, then cut the flesh into two halves away from the pit. Cut the halves lengthwise into ½-inch strips, then crosswise into ½-inch pieces.
• Cut the grape tomatoes in half.
• Cut the avocado in half. Remove the pit, scoop out the flesh, and cut the flesh into ½-inch pieces.
• Coarsely chop the cilantro.

In a medium bowl, stir together 1 tablespoon lime juice and 1 to 2 teaspoons oil. Add the onion, mango, tomatoes, avocado, and cilantro and stir gently to combine. Season to taste with salt and pepper.

• Trim the root end from the iceberg lettuce; separate the leaves.

Transfer the lettuce leaves to individual plates. Top with the chicken and the mango-avocado salsa. Serve the remaining chipotle mayo on the side.