Toss chicken with 1 tablespoon pesto, salt and pepper to taste. Grill chicken until fully cooked (approximately 6-7 min. per side).
Meanwhile, grill bread on one side until toasted (approximately 30 seconds). Remove bread from the grill, spread remaining pesto onto un-grilled side of the bread.
Assemble sandwich layering one slice of cheese, chicken, cheese, tomatoes, and bread.
