Rub each hen with a lime half. Drizzle the hens with olive oil, and season with chili powder, cumin, kosher salt, and pepper. Place hens on a rack in a shallow roasting pan.
Roast hens 15 minutes in the preheated oven. Reduce heat to 350 degrees F (175 degrees C), and continue roasting 30 minutes, or to an internal temperature of 180 degrees F (80 degrees C).
