Preheat the oven to 425 degrees Fahrenheit.
Pat the 1 pound chicken breasts dry with paper towels. Place the chicken between two pieces of plastic wrap or in a resealable bag and, using a rubber mallet or heavy pan, gently pound to an even thickness.
In a small bowl, combine 1 tablespoon brown sugar, 1 teaspoon chili powder, ½ teaspoon paprika, 1 teaspoon Italian seasoning, and 1 teaspoon garlic powder. Stir until evenly mixed.
Rub the spice mixture evenly onto both sides of the chicken breasts.
Lightly grease a 9 x 13-inch pan and arrange the seasoned chicken in a single layer in the pan.
Bake uncovered in the preheated oven for 15–20 minutes, or until an instant-read thermometer inserted into the thickest part of the chicken registers 165 degrees Fahrenheit.
Remove the chicken from the oven, transfer to a plate or cutting board, tent loosely with foil, and let rest for 10 minutes before slicing or serving.