Preheat oven to 450°F. Lightly spray wire baking rack with nonstick cooking spray and place rack in foil-lined rimmed baking pan.

Cut each chicken breast in half as though you were going to butterfly it, but cut all the way through to make two thin flat pieces (4 total). Pound to an even thickness (about ¼ -inch) between two pieces of plastic wrap, or in a zip-top bag, using the flat side of a meat tenderizer, a rolling pin or the heel of your hand.

Add buttermilk to a medium bowl and place the chicken in it.

In a shallow bowl, combine panko, Parmesan cheese, salt, basil, garlic powder, pepper, oregano, and thyme; mix to blend.

Lift each piece of chicken out of the buttermilk, letting excess drip off, and coat it in the bread crumb mixture. Place on prepared wire rack. Repeat for remaining chicken breasts.

Bake 15 minutes, or until chicken is golden brown. Remove from the oven, spoon marinara on top, and sprinkle evenly with mozzarella cheese.

Continue to bake for another 3 minutes or until the cheese is melted and the chicken is cooked through (165°F on instant read thermometer).