Preheat oven to 425°F. Pound chicken to an even thickness. Mix the brown sugar, paprika, oregano, garlic powder, salt and pepper together. Set aside.
Line a baking sheet with parchment paper. Place chicken upside down on tray. Drizzle chicken with about 1 tsp oil. Rub over with fingers. Sprinkle evenly with half of the seasoning. Flip chicken. Drizzle with 1 tsp oil, rub, sprinkle with remaining seasoning, covering as much of the surface area as you can.
Bake chicken for 18 minutes, or until internal temperature is 165°F using a meat thermometer. Allow chicken to rest for at least 5 minutes before dicing into 1-inch pieces.