If using boneless, skinless, chicken breast, slice in half to thin. (Skip this step if using chicken tenders or cutlets.) If, after slicing, the chicken pieces are still quite thick, pound them with a tenderizer to about ½” thickness.
Season chicken on all sides with salt and black pepper.
In a shallow bowl, combine breadcrumbs and parmesan cheese.
Heat cooking oil in a large skillet over medium heat until shimmering.
Working with one piece of chicken at a time, dredge it in panko mixture, pressing firmly to help the breadcrumbs stick. Sear chicken pieces on both sides until golden brown, 5 to 7 minutes total.
When chicken is done cooking, transfer to a paper towel-lined plate.
Stir together all ingredients for tomato and mozzarella salad. Season salad with some salt.
Toss arugula with lemon juice and 2 teaspoon olive oil.
Divide arugula between salad bowls or plates. Top with chicken and serve tomato salad and pesto on top. Finish each serving with some fresh-cracked black pepper.