01 - Preheat oven to 400°F. Lightly grease a 9x13-inch baking dish with cooking spray or a small amount of olive oil.
02 - Pat chicken breasts dry with paper towels. Drizzle both sides with olive oil, then season evenly with salt and black pepper. Arrange chicken in the prepared baking dish in a single layer.
03 - In a medium bowl, combine thawed spinach, chopped artichoke hearts, softened cream cheese, sour cream, Parmesan cheese, minced garlic, and crushed red pepper flakes. Mix until thoroughly blended and smooth.
04 - Spread the spinach-artichoke mixture evenly over each chicken breast, creating a thick layer on top of the meat.
05 - Spoon basil pesto over the creamy spinach-artichoke topping. Spread gently in an even layer, being careful not to mix the pesto completely into the creamy base.
06 - Sprinkle shredded mozzarella cheese evenly over the pesto layer, covering the entire surface of each chicken breast.
07 - Bake uncovered for 30–35 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F. The cheese should be golden brown and bubbling.
08 - Remove from oven and let the chicken rest for 5 minutes before serving. This allows the juices to redistribute. Garnish with fresh basil leaves if desired.