Preheat grill to medium heat, or between 350° to 450°F.
Trim excess fat from chicken, rinse and pat dry using paper towels. If necessary, pound chicken to an even ½-inch thickness using a mallet, rolling pin or cast-iron skillet (this will ensure the chicken cooks evenly).
Place seasoning, oil and lemon juice in a 1-gallon resealable plastic bag.
Add chicken. Seal bag and turn to thoroughly coat chicken.
Brush grill surface with a little corn oil to prevent sticking.
Grill chicken over direct high heat for 6 to 8 minutes.
Turn chicken and continue to cook for 6 to 8 minutes until cooked through.
Transfer cooked chicken to a serving plate.
Combine salsa ingredients in a bowl; stir and season to taste with salt and pepper.
Top grilled chicken with mango salsa and serve immediately.