Preheat oven to 400 degrees F.
Line baking sheet with heavy-duty foil.
Place chicken and pesto in medium bowl; toss to coat.
Place chicken on prepared baking sheet.
Bake for 20-25 minutes or until chicken is no longer pink in center.
Remove from oven; top with tomatoes and cheese.
Bake for an additional 3-5 minutes or until cheese is melted.
