Pat chicken breasts dry with paper towels to remove surface moisture. This ensures proper mayonnaise adhesion and prevents dilution of flavors.
If chicken breasts have uneven thickness, gently pound the thicker portions to achieve uniform thickness of approximately ¾-inch (2cm) throughout. This ensures even cooking.
In a mixing bowl, combine mayonnaise, garlic powder, chopped herbs, Dijon mustard, lemon juice, salt, pepper, paprika, and Parmesan (if using). Mix thoroughly until homogeneous.
Set oven to 425°F (218°C) and allow to fully preheat. Position rack in the middle of the oven for optimal heat circulation.
Line a rimmed baking sheet with parchment paper or aluminum foil and place a wire rack on top. Lightly spray rack with cooking spray to prevent sticking.
Using a silicone brush or the back of a spoon, apply the mayonnaise mixture evenly to all surfaces of each chicken breast. Ensure complete coverage with approximately ⅛-inch (3mm) layer.
Place coated chicken breasts on the prepared wire rack, ensuring at least 1-inch (2.5cm) spacing between pieces for proper air circulation.
Place in preheated oven and bake until internal temperature reaches 165°F (74°C) at the thickest part, approximately 20-25 minutes depending on thickness.
Remove from oven and allow to rest for 5-7 minutes before slicing or serving to redistribute juices and complete carryover cooking.