Pat dry the chicken: Remove the chicken breasts from their packaging and pat them completely dry with paper towels, about 1 minute. Dry chicken browns better and cooks more evenly.
Coat with oil: Place the chicken on a baking sheet lined with parchment paper or foil, then drizzle with olive oil and rub to coat all surfaces evenly, about 1 minute.
Season generously: In a small bowl, combine the light brown sugar, chili powder, cumin, paprika, garlic powder, and cayenne pepper. Sprinkle the mixture generously over both sides of the chicken, pressing lightly so it adheres, about 2 minutes total.
Add salt and pepper: Season each breast with kosher salt and freshly ground black pepper to taste.
Preheat the oven: Heat your oven to 425 degrees Fahrenheit, about 2 to 3 minutes.
Bake the chicken: Place the seasoned chicken in the preheated oven and bake for 12 to 15 minutes, depending on the thickness of your breasts. The chicken is done when the internal temperature reaches 165 degrees Fahrenheit when measured with a meat thermometer at the thickest part.
Rest briefly: Remove from the oven and allow the chicken to rest for 2 to 3 minutes before slicing or serving, which helps retain juices.
Drizzle with lime juice: Squeeze fresh lime juice over the warm chicken breasts, adjusting the amount to your taste preference.
Garnish with cilantro: Sprinkle the finely minced fresh cilantro over the top just before serving for maximum herbaceous freshness and visual appeal.