Sprinkle both sides of chicken with oregano, and season with salt and pepper, if desired. Heat Olive Oil in a large (12-inch) skillet over medium heat. Add chicken to pan, skin side down; cook until skin is browned and crisp, about 8 minutes. Turn chicken over, and increase heat to medium-high; cook until chicken reaches 165°F, 8 to 10 minutes. Remove chicken from pan.