01 - Preheat oven to 400°F. Lightly grease a 9x13-inch baking dish with cooking spray or a small amount of oil.
02 - Pat chicken breasts dry with paper towels. Drizzle both sides with olive oil and season evenly with salt and pepper. Arrange in the baking dish in a single layer.
03 - In a medium bowl, combine spinach, artichoke hearts, cream cheese, sour cream, Parmesan, minced garlic, and red pepper flakes. Mix until thoroughly blended and smooth.
04 - Spread the spinach-artichoke mixture evenly over the top of each chicken breast, covering completely.
05 - Spoon basil pesto over the creamy topping on each chicken breast, spreading gently to create an even layer.
06 - Sprinkle shredded mozzarella cheese evenly over the pesto layer on all chicken breasts.
07 - Bake uncovered for 30 to 35 minutes, or until chicken reaches an internal temperature of 165°F and cheese is golden and bubbly.
08 - Remove from oven and let rest for 5 minutes to allow juices to redistribute. Garnish with fresh basil leaves if desired.