In a large skillet, heat the remaining peanut oil over high heat until almost smoking. Add the chicken breasts, skin side down, and reduce the heat to moderately high. Cook the chicken until the skin is nicely browned, about 3 minutes. Turn the chicken and add 1 cup of water and the sugar. Cover, reduce the heat to moderately low and simmer until the chicken is cooked through, about 8 minutes. Transfer the chicken to a plate.