Open package of chicken* and drain off any excess liquid.

Heat a drizzle of oil in a large pan over medium-high heat. Add chicken; season with salt and pepper. Cook, stirring occasionally, until browned and cooked through, 4-6 minutes.

Turn off heat. Transfer chicken to a large bowl; set aside to cool slightly. Wipe out pan.

Melt 1 TBSP butter (2 TBSP for 4 servings) in pan used for chicken over medium heat. Add panko; season with salt and pepper. Cook, stirring constantly, until golden brown, 2-4 minutes.

Wash and dry produce. 

Halve tomatoes. Trim and discard root end from lettuce. Reserve 6 large leaves for serving (12 leaves for 4 servings); thinly slice remaining lettuce.

To bowl with chicken, add tomatoes, shredded lettuce, pesto, and mayonnaise; stir until thoroughly combined. Taste and season with salt and pepper if desired.

Divide reserved lettuce leaves between plates; fill with pesto chicken salad. Top with toasted panko and serve.